I think it's because it gets over whelming at a point. It's hard trying to fix issues when the angry mobs don't know what they want and say "FIX THIS. YOU LAZY SHITHEADS". Fix what? They're more specific with negative words that they're calling Treyarch , than the complaint itself.
MW, she got death threats and probably even sexual abuse threats, I'd stay tf away too. It's a lot to take in, they're human. We need to realize this. They can get doxxed if someone was pissed enough.
Keep in mind, they're only reporting back what Treyarch/IW has told them. There's no guarantee. We're not in their shoes. We simply play the game and post about it on reddit.
Treyarchs communicator even said /r/Blackops4 was just too toxic.