It seems like lemmy picked up the bulk of the refugees so far. Shifting again would be risky at this point, it just serves to dilute the numbers again. Some stay, some go etc.
I firmly believe this is only the beginning here. Reddit is probably fine to lurk so long as old.red*it.com remains, but it has become a pretty hostile place for people who participate.
My prediction is that reddit will just end up hosting content posted by bots and commented on by different bots and nobody will have any idea that there's so few real users left. This will become the home for actual discussion between humans.