My reason why i don't like MW is
The multiplayer was actually alright at first but then became bad very quick. I cant stand it because of the SBMM and the campers.
The campaign was okay but most of the other games have better campaigns. The villain was very generic and the characters were just mediocre all around.
The spec ops was absolute shit, a complete disappointment compared to MW2 and MW3
Warzone is alright but I'm not really into battle royale games.
And my reasons for liking IW
Well the campaign was good imo, I did think the villain was disappointing but I enjoyed mostly everything else
The multiplayer was fun and had no campers or SBMM, although I dislike the supply drops
Zombies was also good imo, not as good as the previous treyarch games but I think it's the best non treyarch zombies.
Sure the games is futuristic and doesn't feel like a COD game but I enjoyed it