I don't see much of a need to frame it as "breaking into his car" because I don't think what you do with your own property has an inherently negative connotation to it, one which Cops could use to be persistent in UNreasonable suspicion. Breaking into his car, breaking into his house because he lost his keys, going back to retrieve a wallet HE dropped on the ground, or let's say...working in his own store after hours:
They were harassing him, suggesting he needed to prove he is innocent, and then suggesting he should be thankful for it. And I'm talking specifically about this concept that Police feel they can go beyond their actual abilities to obtain identification, there's a good reason there are not only Constiturinal protections against this, but relevant case law further defining it and backing up the notion that Police CANNOT force you to identify or incriminate yourself, nor can they perpetually extend an interaction to try to ascertain your guilt.
I think what I outlined is perfectly fine police work if you dont look at justice as something that needs to be won, or if you arent entirely sympathetic to the idea that a Cop NEEDS to feel like they're about to be a hero every time they see a citizen doing something abnormal. Again that lends to much to the notion that Cops arent there to help, they're there to punish. There was NO need to punish this man for having to enter his own vehicle in an unconventional manner, especially considering he didnt owe them any further information than what was provided. He explained what was going on, he offered corroboration, and he didn't object to their presence. He just told them he wasn't going to identify himself, and they kicked his ass for it. I'm sorry but that's far worse policing than what I listed.
Moving into a "prove you're supposed to be here" or "prove to me you're NOT committing a crime right now" territory is dangerous. Suggesting Cops proceed as if every citizen is tentatively lying to them enhances that danger. IMO Police should make informed decisions looking at the totality of the situation, rather than this...which is reacting based on feels. Or at best, poor logic. Like this scenario:
Again, arrested for not ID'ing when not committing a crime. This is nothing more than the old "we came here, so someone is getting punished."
She was aware she doesnt owe them to prove her own innocense, even in the face of threats of destruction of her property.