Obviously a few years ago, the API changes caused the reddit community mods to strike, and caused a mass-blackout of most reddit core communities. Eventually Reddit removed a handful of mod teams on some notable subreddits and caused the rest to chicken-out. But it did birth the Fediverse properly.
I suspect Reddit will make another step at some point which causes another comparable exodus. This time, if they do, the Fediverse is far better developed to handle it. What do you imagine it might be?
I think most of the people who are going to leave have left. Its no longer a matter of an exodus because the people who are there now aren’t the kind of people who can build a place like Reddit. Those people, we, the people, have left.
So the “next big exodus” is really about there being a newer/ better place to go for the same experience.