Comment by anal_reactor

The core issue is that now the internet is full of non-technical people so you're not getting the critical mass to make self-hosting a thing. So you absolutely need a platform. And when there's a platform, there is social pressure that the admin should ban certain types of content. Once people decide to ban some content, it's a matter of time before the tides shift and you have a huge crowd screaming "I never thought that Leopards would eat MY face!".