That's one of the reasons centralized model works so well nowadays, nobody wants to take care of things anymore, self hosting your own apps is becoming a small niche
I mean, why would you? It is quite a bit of technical hassle, even for an experienced admin. There's quite a bit of cognitive load just deciding what software stack to use, even before you run an installer. And then you have to maintain it too!
Compare that to less than 3 minutes of sign-up and creation of a new subreddit. It is an orders of magnitude difference in effort and knowledge required.
Security would be less an issue than back then, too. We learned a lot since early PHP and early Javascript's bad practices.