Minecraft is an exception, pixel-y graphics that most would consider bad
They are pixely, but they aren't really "bad" either. It's more unique than anything. I mean, seeing that boxy cow move past you with inaccurate leg movements is hilarious, but you still know it's a cow the second you see it.
There's also the option of HD texture packs which increase the resolution on each block from 64x64 to like 256x256 or more. While stuff is still blocky, the individual textures aren't bad.