I think self-hosting is great for people who understand computers, but for the larger populace, it may be more important to find hosting providers who are non-profit. That’s what I’m trying to do with Posthaven. Surely computing technology and storage costs will come down to a point where a paid service can simply pay for all content being stored forever.
Then at that point the only thing you have to worry about is whether or not the software is good. And there’s no reason why software of this kind can’t be as good or better than what you expect from for-profit corporations like Facebook or Google.