That’s exactly what Bluesky was designed for: so that anyone can clone their qubibytes of data and start a new central platform anytime without any account loss (though this mechanism relies on user domain owners staying the same). You can read more at https://dustycloud.org/blog/how-decentralized-is-bluesky/ from the ‘Bluesky is centralized, but “credible exit” is a worthy pursuit’ section on.