Donald Trump takes counsel from absolutely nobody. Of all the enemies he sees around him (and there are a lot), none is more formidable than himself. And these aspects of his character are insuperable. I don't think he's ever even considered the possibility that he was wrong about something...or that somebody else might know more about a subject than he does.
And, of all his many flaws, this is almost certainly the most problematic.
I was a little bit hopeful that he would choose somebody like DeSantis, Haley, or even Burgum as his runningmate -- somebody who strikes me as being a plausible POTUS. I've never been a big Mike Pence fan. But he at least cleared that bar. Nothing against JD Vance as a person, but he doesn't exactly strike me as being cut out for that office. And I can't honestly say for sure that this wasn't a feature, rather than a bug, of his being chosen.
It's not hard for me to understand why there are prominent conservatives who would rather have a left-wing POTUS than Donald Trump. And I'm not talking about the RINO types. I mean actual, card-carrying conservatives.
Personally, I can't see any compelling reason to vote for Kamala. Most of her policy ideas (even the "moderate" ones) strike me as awful. But it's not enough to get me to pull the lever for Trump again.