Ringo & Springsteen made a commitment to do the gig in NC.
People spent their hard earned money to buy tickets.
You DO THE GIG. If you have some problem with the policy that doesn’t mean you don’t honor your commitment. If you want to rant about it on stage go ahead, but don’t be a coward and not play just because you don’t like it.
Celebrities rant on stage for all sorts of causes to an audience and then play.
I think the celebrities are doing this as convenient virtue signalling, to look good, not actually out of conviction.