Indie games have been pretty blatant with their appropriation of pixel-based art styles, so much so that it's started to become a bit of a joke. If you were to take a drink every time there's a new indie game or Kickstarter announced that uses the term '16-bit graphics', you'd be dead in 5 minutes. Life of Pixel takes that whole thing a step further by taking you through the evolution of pixel art, such as the Commodore 64, the NES and the Game Boy.
The graphical stylings seem pretty spot on, but as with all things like this, there's several spots that make you go "I don't think that system could have handled something like this". The NES and Game Boy parts in particular have this (mostly because these are the consoles I'm most familiar with), where there are just things that are too smooth, in terms of shading and pixel work and animation. And no sprite flicker! But I'm not going to hold this against the game. It wants to be in the style of these systems, not an exact representation (though the jump sound when you start up the NES does sound AWFULLY like a certain famous jump sound...), and it achieves that well enough. It's a game based on your memories, not real history, so it wants you to bask in the fuzzy glow of nostalgia instead of going "oh, I can do that thing like in Blaster Master where I just pause and unpause a punch of times and everything dies!"
What I think is more interesting is that they also chart the evolution of the size of the games and some of the technical achievements. When you start out, there's only one screen, and it doesn't even scroll. You can jump and avoid enemies, but you just have to collect things and go. One giant room. And this persists for a while until, like it would in the actual evolution of games, until that excellent day when it becomes possible to jump between different screens, like in Pitfall or Adventure. The limitations of this soon prove cumbersome, but thankfully, scrolling levels aren't too far behind it. It's actually more fun to see where the game arbitrarily throws things in, and it makes you consider how far games have come, even in changes as small as that.
Although I think it's a little odd that since the main character is a pixel, ostensibly he should be shrinking and able to do more as pixels shrink and are able to do more, right?
Part of the evolution of consoles, after all, is the way they also allowed for new kinds of gameplay, but Life of Pixel never seems to care about that. By the time we got from the Atari to the NES, video games had changed dramatically. The Crash had happened. PCs had become more powerful and consumer friendly. Arcades were ridiculous things that just kept upping graphical power and gameplay methods in an attempt to get quarters out of you. But while the graphics may get overhauled, the gameplay never does in this game.
So when you start out, you're collecting all the glowy things until a door opens and you can exit. And then you keep going and doing the exact same thing until you're done. And it's not exactly fun. They don't really make games like this anymore because it's a super old style that we've grown away from. Platformers are more involved than that. Even similar pixelated platformers have gone different ways. But instead you're just going to never stop doing the same thing until you stop playing the game.
Worse, the game keeps setting you up in situations where you can't see the platform you're supposed to be jumping to, so your first couple of tries might involve a death that you don't expect because you couldn't see the danger below. It's especially bad when areas have spike traps that you don't know about until they're stabbing you to death, or enemies who are walking below you and you can't see them. For some reason, you also can't move the camera, so you're just having to take a chance and see if it works out. They aren't really fun deaths because then you have to repeat the entire level over, and all you learned was "oh the developers purposefully hid that death from me, knowing that I couldn't react." You're just stabbed to death, restarting the level.
Since the gameplay is so uninteresting, you've got to ask yourself: how interested are you in a game that's just a nostalgia piece for old graphics and music styles? It's cool if that's what you want, but like I said earlier, a lot of indie games have already coopted pixel-based graphics and music, and it's not hard to find stuff that'll scratch some kind of itch. There are excellent sites like 8bitpeoples that let you listen to chiptune music for free. I guess the big draw is supposed to be that you can play several different 'systems' in one place, like a museum, but the gameplay isn't good enough to really stick through it. Video game history is certainly interesting, and preservation of the medium is something to be talked about, but this isn't even a game that attempts to address that, instead just asking you to remember a time when graphics were like this and games weren't so complicated.
Also, special shoutout to the music, which is all composed either on the actual console, or on emulation. That's super awesome! It's certainly one of the better parts of the game.
Life of Pixel could have been something more ambitious, like Evoland, but instead chooses to play it as straight as possible. It almost seems to be suggesting that graphics change, but gameplay doesn't, because through the levels you're still doing the same boring 'collect all items then go to the exit' thing that you were doing on the ZX81 at the beginning. Maybe it gets prettier, but it doesn't do enough with the concept to be worth your time, unless you're just that desperate for a game that tickles your nostalgia. Even then, there are way better experiences out there.