If you have an 'old' Twitter account you don't want deleted for archive or impersonation reasons, then it's probably worth logging back in once and following Elon.
Bet you cash money the Twitter devs will write any delete queries in the next few months with an 'unless they follow Elon' clause.
Do YOU want to be the one explaining to the Narcissist-In-Chief why his follower count dropped?
(Also download the archive of your old tweets if there is good reason to preserve them for the future)