This is exactly right. Which brings us to the 'half-baked' option of self-hosting anything. For example, if you self-host a matrix server for you and your friends and family (assuming you're able to get them to use it), your data, on your end, is relatively safe and you're in control, however, the others may have their devices compromised either by Google on stock Android, Microslop on Windows or iOS on Crapple devices, so whatever you share with them is still at risk of being gathered by these tech giants anyway. It's a very hard problem to solve. The technology for the solution is there, but it's unrealistic to expect everyone to just drop everything they know and are used to, since lack of convenience and friction is just too much for most normies to even attempt to deal with.