If you personally get no value from posting on X then you should stop. I don’t mean financial value, I mean happiness value. Do you enjoy using it?

It sounds like you don’t because of the poor engagement. Since they already have your KYC info, deleting it won’t give you back your privacy. Putting your nostr profile in your X bio and just going all in on nostr is what I would do. The only reason to delete is if you’d like to send a symbolic fuck you to Elon and the establishment.