I disagree.
I don't think 90% of his diehard supporters would place personality above the Constitution.
Some would of course, the same easily led, low IQ boobs that are too lazy, uninformed or stupid to make up their own minds on anything and will do whatever they are told.
For many, the 2nd Amendment is one of their primary reasons for voting, and there would be a huge upheaval in the Republican party if Trump tried that. There would be no repercussions for him politically since he will be a lame duck.
He could potentially be removed from office if the Republicans were sufficiently outraged and Vance would likely undo whatever Trump did to institute a registry/ban in the 1st place, since there are not enough votes in Congress to pass such a bill.