Which is, I understand, why Trump makes you cringe. I’d cringe even worse at Trump if I didn’t watch how his stories play out. He bites off your head one week and then is fine with you the next week once the crisis of disagreement is over. It isn’t personal. I’d sooner err to the undiplomatic side, however, when facing obdurate opposition. The audience matters, and to be fair, Trump doesn’t do this a lot to friends. That’s analogous to why seeing Cruz (whether directly or by proxy) do it to friends hurts.
Trump makes me cringe for a whole host of reasons. You mention just one.