You're going to leave security, data integrity and privacy compliance up to random unaccountable anonymous strangers on the Internet who self-host?
You're going to trust them to have proper backups, proper disaster recovery, proper resiliency and scalability?
What you're describing works for small-time stuff like blogs, personal projects or other inconsequential things, but anything at the scale of Goodreads, where users are trusting years of data to someone just can't be hosted by random people.
I'm not saying I have the answer but "people should self-host this kind of thing on their Internet connections" is not it.