I have my small little groups. I've walked away from big sites constantly and this won't be an exception. Definitely going to cancel my Nitro today until/unless they revert this.

But leaving is never free. There's a lot of gaming communities (especially niche subcommunities like emulation, speedrunning, modding, etc) that are mostly on Discord and not anywhere else. Many probably won't move. A lot of tribal knowledge will be lost as it's locked in these communities.

Heck, even some FOSS communities communicate mostly on Discord. I have more faith they will move. But not all.