In getting a feel for the zeitgeist, it's a mistake to look at any medium isolated from all others, especially if they appeal to the same sense, like visual media. I've gone over some of the major changes in the visual culture elsewhere, and this post will not be a summary of all that. It will only establish a pattern at the low level. Sometime later I might provide links and general discussion to all of the low-level pieces that fit into the general picture.
No way I'm going to review the graphics of every video game ever made, so I'll try to stick with popular and representative games, what resonated with the general audience. As with movies, still images from one part of a game may not look like another part, and delightful visuals come out more in the playing and animation. But they do give a hint of its visual style. And I'm limited to images that I can quickly find online. So there won't be a Hall of Fame and Shame feel to the images here; just a series that will highlight some obvious differences between then and now.
I won't be including images within this post because they'll take too long to make, and I could be accused of taking unrepresentative shots from the game. Instead I'll mostly link to a screenshot at GameFAQS, which you can open in a new tab, and if you want, explore the rest of the shots by clicking on the light blue tab that reads "Imgs" or "Images". The first two links in each topic will be to games from the 16-bit era and earlier, the second two from the 3-D era.
Striking visuals make use of contrasts, so I'll go through some of the most common contrasts and show how they've become more muted over the past 15-20 years. "Striking" simply means attention-getting and memorable, not mind-blowing.
Bright vs. dark lighting. I don't know if early video games could independently vary both the brightness and the hue (red, blue, yellow, etc.). A simple way to achieve this is to make the background black or another "dark" hue, and the characters and terrain in the foreground white, red, orange, or other "bright" hue.
Such contrasts used to be common, though not pervasive, whereas now when the designers can fool around with the lighting, it tends to be uniform -- all bright, all dark, or all in-the-middle. In almost every screenshot or video clip I've seen of games from the PlayStation / N64 era to today, I can't tell what I'm looking at. Figure vs. ground, background vs. foreground, etc., all just blends in to each other. And the uniform level of lighting is part of that. Nothing stands out from different intensities of lighting. Worse than being uniform, it's usually uniformly dark.
Image - Streets of Rage II (Sega Genesis, 1992)
Image - Super Metroid (Super Nintendo, 1995)
Image - The Legend of Zelda: Ocarina of Time (Nintendo 64, 1998)
Image - Call of Duty: Modern Warfare 2 (PlayStation 3, 2009)
Hot vs. cold hues. This contrast pits the hues closer to red against those closer to blue. Starting again with the PlayStation / N64 era, video games gradually let the full color spectrum fall into disuse, let alone juxtapose opposites. That used to be normal before. This may have something to do with the more naturalistic approach to video game graphics, but I don't think that's the main reason. Why not have the characters wear clothes with strong color contrasts? They're not only trying to look naturalistic but also contemporary -- and people dress in such drab colors today. Same with architecture, cars, devices -- no colors, let alone contrasts. So here we see video games directly reflecting the larger visual culture.
Image - Mega Man 3 (Nintendo, 1990)
Image - Sonic the Hedgehog (Sega Genesis, 1991)
Image - Resident Evil (PlayStation, 1996)
Image - Grand Theft Auto IV (PlayStation 3, 2008)
Shallow vs. deep staging. By trying to attend to too much detail across a deep range of distances, we get lost. The most striking paintings do not exploit deep 3-D perspective very much -- that diffuses our attention across too much space. Restricting the number of distances that we're supposed to take in makes it much easier to focus on the important stuff, and perhaps build up tension.
Nothing required a switch from 2-D to 3-D graphics in video games. In fact, a number of 2-D games were made into the late '90s on home consoles, and later into the 2000s on handheld systems only. (Although even there, the new Nintendo 3DS shows that soon even handhelds may show mostly or only 3-D graphics.) Rather, audience tastes changed during the mid-'90s, explaining the widespread adoption of consoles with 3-D graphics.
I found them boring to look at -- like Atari in 3-D -- and didn't bother with most games after then. Earlier games made use of two planes only -- one up close where all the action was happening, and a distant background to set the atmosphere, not always with much detail (perhaps just a monochrome light blue plane for "the sky").
Image - Zelda II: The Adventure of Link (Nintendo, 1988)
Image - Super Castlevania IV (Super Nintendo, 1991)
Image - World of Warcraft (PC/Mac, 2004)
Image - Assassin's Creed: Brotherhood (PlayStation 3, 2010)
Exotic vs. familiar imagery. All familiar looks too everyday, not particularly worth attending to, while all exotic looks so remote as to be irrelevant to here and now. Combining both gets your attention -- you weren't expecting the one world and the other world to bleed together. This tends to employ contrasts across different geographical regions, but could also be across time, or both.
In contrast to earlier games, recent ones are split into either familiar settings and imagery or fantasy settings and imagery, with little of the eclectic here-meets-there style. You see the same thing with the look of movies, either the pure remote fantasy of Lord of the Rings, Harry Potter, and Avatar, or the pure familiar realism of Saving Private Ryan, Spiderman, and Twilight.
Image - Forgotten Worlds (Arcade, 1988)
Image - Strider (Arcade, 1989)
Image - The Sims (PC, 2000)
Image - The Elder Scrolls V: Skyrim (PC, 2011)
Large vs. small figure sizes. Most video games today don't even place human-sized characters against gigantic natural or architectural environments to create a sense of the sublime. Occasionally they do, though, since that is allowed under the naturalistic approach. Earlier graphics contrasted the size not only of the character and the environment, but of the characters themselves.
Typically that was saved for tougher enemies and for "boss fights" at the end of a level, where the thing you had to fight to clear that level would often be twice your size or larger, sometimes filling a good chunk of the screen. The main thing needed to create tension and give you a sense of achievement after defeating the boss is just making them hard to kill -- stronger attacks and a tougher defense than the enemies you're used to. There's no reason the boss has to be huge, but it amplifies the tension for the largely juvenile audience that video games are made for.
Generally you only see figure size contrasts in the pure fantasy games today, which aren't a very popular genre. In the late 1980s, even a boxing game like Mike Tyson's Punch-Out featured opponents who were more than twice your size.
Image - Altered Beast (Sega Genesis, 1989)
Image - Mega Man 2 (Nintendo, 1989)
Image - GoldenEye 007 (Nintendo 64, 1997)
Image - Left 4 Dead 2 (PC, 2009)
Saturated vs. dull colors. In this case, striking visuals come from picking one side rather than juxtaposing both in a contrast. Rubens' paintings are more striking than Rembrandt's because, even though both may exploit light-dark contrasts, the same hue will be more vivid or full in Rubens' and more muted or subdued in Rembrandt's.
Since the PlayStation / N64 era, video game graphics have taken on a totally washed-out look, which compounds the problems of having uniform lighting. It makes it even more difficult for the important things to stand out from the less important ones. Earlier games did not have a pre-school level of super-saturated colors, but were still more in that direction, giving them a more vivid look.
No additional images for this one, since you've already seen the washed-out vs. vivid look in the ones above.
Repeated design motifs. Also not a contrast, but another hard-to-miss difference between earlier and more recent graphics. Repeated design motifs make an image more memorable (catchy), at the expense of naturalism. Their presence gives earlier games a more primitive tribal art / crafts kind of look, more ornamental and geometric than purely representational. And given that video games can't (yet?) reach the representational level of painting or photography, they might as well play up the geometric look, like jewelry, clothing, "products," furniture, and architecture.
Image - Contra III: The Alien Wars (Super Nintendo, 1992)
Image - Sonic CD (Sega CD, 1993)
Image - Super Mario Sunshine (Nintendo GameCube, 2002)
Image - Batman: Arkham Asylum (PlayStation 3, 2009)
Video games are squarely middle-brow and for juvenile audiences, but that doesn't mean they don't count in a larger account of the visual culture. Their increasingly dull look since the mid-1990s has deprived young audiences of what could have been something exciting to look at, comparable to the concurrent decline of poster art, album cover art, and book illustrations.
And of course there's the chicken-and-egg problem that young people these days have much more boring tastes to begin with than their counterparts of 20 to 30 to 40 years ago. Sometime soon the next crop of youngsters will have somewhat cooler tastes, and it will be interesting to see what video games will look like as they shift back toward accommodating audiences who want striking visuals, but this time around with a richer set of technology at the designers' disposal. Doubt I'll be enjoying them personally, but it'll be heart-warming to see young people once again getting into something fun rather than dull.