This is essentially why there are a small number of “legacy” web sites that never got subsumed into the oligopoly - they have communities, the communities host content creators, if you want the fresh content you have to be where they are.

The thing that allowed communities to end up on Facebook, Reddit, and Twitter was mostly a matter of traditional forum hosting being a challenging, technical thing with ongoing maintenance tasks and one account per forum you wanted to visit, instead of “button press and we do the rest”.