I can think of three people this happened to, one is back on X, another no longer uses social media and the last is on blueSky.
Cool fun people, but I can see why they decided it was "too confusing" and "dead."
These are only the people I kept track of, I suspect there are 1000s of dead accounts that are created due to this totally confusing aspect of the interface. Happily this only seems to happen on the web, and the phone apps are more popular.