B04 was under appreciated in its day for sure like IW. Both IW and B04 have grown in appreciation/love in the community the further we get from there lifecycles.
Honestly I would say the opposite, the hate was kinda warranted back in the days. The game crashed a lot and the battle pass system that wasn’t progressable when playing zombie for like the first half(?) of the cycle was kind of a joke. Although it is also to blame partly on the community, for being simple-minded and not accepting changes like the perks. Although even that, was understandable in the beginning. But with the semi-jugg added later, speed cola as a bonus for having all perks, and double tap available through multiple pap’ing was nice additions and really you don’t miss much when playing now and you got used to it.
On top, the variety for perks is just fantastic to have. If you’ve gotten used to it, it does suck hopping back into bo3 and having to get the at least 3 crunch perks simply because you have to.
On bo4 there might be perks you run all the time because they suit your play style but there’s so much that I see different people playing. For example I see people swear on dying wish while personally that isn’t good for me at all. There’s just so much you can do with the system and it’s great.
If the game released in it’s final state now it would be like literally the best thing to happen to zombies.
I wish we’d have such high quality maps again