Do you have enemies that would be interested in spending real money trying to link your public accounts to some (possibly existing, likely not) alt accounts with "personal things"? I don't think that's very common.

And no, while I'm sure LLMs can be used for stylometry in academic exercises, I don't think they'll really enable any sort of automatic mass-deanonymization of random social media accounts. But who knows, the US government probably has a bunch of new PRISM-like programs going on already, so it might happen.