Conversation

I think it's a bit of a misused and overused trope to say that people use centralised services because they have a better user experience.

The only definition of user experience that puts Facebook or Twitter ahead of alternatives is a broad definition that includes the network effect (people I know are on it) and familiarity (it's what I'm used to).

But in such a broad definition, I would then include things such as 'you manipulate me with ads', 'you steal my attention'. This is bad UX.