You're neglecting the tools and bots that use the API, which are heavily utilized by most mod teams. One of the pillars of reddit is unpaid moderators, and if the tools that make that job doable on the scale of reddit stop working, then you will see a mass exodus of those unpaid moderators. That means the death of most of the big, well moderated communities like AskHistorians, AskScience, AITA, etc.
I've already seen many of these subs having moderator led discussions about relocation options for the communities.
I've already seen many of these subs having moderator led discussions about relocation options for the communities.