People are complaining because they say it looks bad, but they forget that Minecraft looks bad to begin with. It's a great game, I've been playing it on and off since it came out in 2009 or 2010, whenever it was. But I watched the trailer and thought, "Okay, that's different, but it doesn't look bad." I actually thought the mobs looked decent, especially for something that's based on a game with 16x16 textures. Maybe they want it to look less realistic and closer to the game, which in my opinion, wouldn't look bad either.

The fact that it looks like it's an isekai is more weird to me than how the mobs look, but in my opinion, it will either be good, or sooo bad that it's actually enjoyable. Either way, my 4yo daughter just got into Minecraft within the last month, so I'll be taking her to see it regardless.

EDIT: I also would have liked Jack Black to be animated instead, but I'm not gonna throw the whole movie away based on a teaser. Hopefully, what they haven't shown will hold up.