How about you set up your private node? There's no one stopping anyone. You say. True. But how is that any different than spinning up your own server and centrally host everything on your terms?
The difference between joining a global peer-to-peer network to store data on a public, permissionless, decentralized and immutable database should be pretty clear. If you understood that is what happens by having your own node, then maybe explain how having a private node and spinning up your own server and centrally hosting everything are similar?