The state of Vermont's gubmint networks got hit by this in a major way.
"This is exactly my point; how is this not being deliberately truculent"
There is nothing wrong with refusing to identify oneself unless doing so is illegal. In this case, refusing to identify oneself is not illegal. The job of the police is not to combat random truculence, but to prevent crime/arrest those people who commit crimes.
"short of just letting this guy get off scot free, is there anything that the police could legally have done?"
You only get off scot free if you've done something wrong. He did nothing wrong. He therefore did not get away with anything.
Not only is there nothing the police legally could have done, there is nothing the police legally should have done. Apart, that is, from nothing. Which is what they should have done.
Nonesense, did you even read what you linked to?
In proceedings against any person for the offence of failing to produce a licence [F35 and its counterpart] it shall be a defence for him to show that--
within seven days after the production of his licence [F35 and its counterpart] was required he produced [F36 them] in person at a police station that was specified by him at the time [F37 their] production was required
Except that every additional gigabyte is useful - you can store almost 3 45-minute TV episodes on that. By packing more pixels, however, there are rapid diminishing returns as you start to overcome the resolution of the eye itself.
Time to take stock. Go home with some office supplies.