As major social media platforms morph into comic parodies of their former selves people who want to express original ideas will continue to seek alternatives that avoid the warring robot hordes and put them back in charge of regulating their own expression. Over the next few years I find it possible (though maybe not likely) that the biggest changes in online expression could be a return to personal sites and blogs. This is a viable alternative considering the latitude of expression possible, both in form and content, and the ready availability of interlinked comment and discussion systems.
There are some annoyances and responsibilities inherited with managing one’s own site, but to those for whom expression is paramount and “follower” count is not a primary goal personal sites provide everything but a captive audience — and finding an audience today, now that Google’s monopoly on search seems to be breaking in at least some communities, is not anywhere near as hard as it once was.
Until a distributed alternative to gated-community style social media comes along that is low-friction enough to find gain mindshare among non-tech types (something I would love to create, but currently lack the time) it seems likely that some combination of personal sites, aggregate sites (group-run news/op-ed blogs), blogs, non-YouTube video shares, and alternative social media sites will be the home of most censor-averse communities.
It will be interesting to see how things turn out.