"if he was going to bluff draws wouldn't he bet the turn?" - you can ask the same question about the top of villain's range and I'd argue that it is very unlikely that he's checking back strong hands on the turn. Taking a free card with a draw however, is not out of the question though (regardless of it being optimal or not). That's why I think most villains should be somewhat bluff heavy on the river and therefore, I like your line even if you're not getting the best odds in the world.

Tons of handed missed and their pot size makes their holdings very polarized. I'd be playing it the same way.

Yeah I like a call on the river. Be sure to make a note though once it goes to showdown, could be some valueable information

He showed down JTc. What sort of note would you take and how would you utilise that note in the future?

The problem I have with taking notes is we knew he was polarised here, so I don't want to be folding if he pots it because he did it before

We can't really know much about his river frequencies so as you said "pot bet river = polarized" is kinda redundant, so I'd focus on the flop since min-raising with top pair is not exactly standard.

I like your line, folding to the minraise on the flop can't be right. The river is questionable and I think both folding and calling is alright, calling has more benefits since you get to see his hand so you're kind of paying for the information too for future hands.
Taking notes is easy, just make a note that he had it when he potted river, went r / x / b . Also you don't know he was polarised, maybe he never bluffs in these spots and only pots for value, so make a note of that. Most fish don't use the same sizing for bluffs and value, and most of them don't bluff this way.

I think I'd play it the same. I'm not thrilled about flop but it seems like the best way to play it given the odds. On the river I can tell you my exact reaction would be:

wtf
sigh
call
take a note

These types of villains are often unpredictable enough that I can't narrow their range to only JT or JJ which are probably the only hands that makes sense.

If someone told me fold river was better though I probably wouldn't argue with them.

As the flush draw missed we should just call this river. We block straights and 2 pairs won't always bet this size and we block them again of course.