IDK , my gut tells me the next trend is service hipsterism. where the same megacorporations puppeteer enormous amounts of smaller services that describe themselves as "lightweight", "opinionated" , "carbon neutral" , "poweruser friendly" and some such buzzwords targeting different demographics while decrying the "bloated" main platforms.
All while the mainstream big platforms retain most of the users' "main" profiles still and benefit from having easy "interoperability" with these social media "startups", so as to not miss on any of the data. A sort of controlled opposition. Like brands.
Also you gotta remember that if you can't tell humans from bots,by conditioning them through their social media interactions, that makes humans more predictable and so the data used to cast predictions or mold behavior, more valuable. The bot noise is an externality that can be dealt with at a technical or legal level.
When faced with the problem of online spaces being dissonant with real life, the answer is to make real life more like social media. Their business isn't failing, it's you that's falling behind the times. In time the young'uns will wonder how did you even manage without the interface in your brain that lets you snapshot, archive and replay zongabytes worth of memories on the cloud.
Whose cloud? That's an old person's question.
Security? Privacy? You pay Amazon for that.