fwiw i have and would consider again shipping 40bbs+ as a 3bet with aa/kk. and it's spots like your utg 4x which are spots i think it can be optimal.
it looks like you're never/rarely folding. 4bbs is considered a massive raise online these days as that stage of a tournament. you said yourself you don't think he has kk/aa as he'd just re-raise and not ship. so sometimes I just ship as people with put you on ak etc.
but it is more likely that he doesn't have kk/aa so you're ahead of his range. can't fold.
I open wider than your mother's legs.