I do think some of the larger ones may end up being their own instance in the federation, both to help reduce burden, and to help ensure stability of their content. It will be interesting to see which ones are able to be self-funding through donations (or even ad monetization/corporate sponsorship in some edge cases.)
After enough time in /r/arborists, they must just be sawing off the useless and unhealthy bits so things can grow better!