Part of me feels it's never a bluff here when they raise the river. Other part of me feels what hands 3 bet preflop that make a flush on this river that doesn't bet the flop? If he had KTh, KJh, AQh, KQh, AJh, AKh. they all bet the flop right? Hindsight feels like I got bluffed, but pattern recognition usually shows they have the flush.

I think fold is right ,the hands you win would not 3-bet you at the river ,like JQ ,Qx.

Esp. AJhh/AKhh is a somewhat decently often check-back OTF, right?
He btw. polarized his range by 3betting pre (even though the range is linear; basically any kind of raise is somewhat polarizing between fold/raise).
So if a polarized range checks back a board that favors its range, i rarely expect bluffs on later streets: Usually they would be starting to bluff OTF i guess.

Am I over cbetting? If I was the btn I would likely be betting most of my 3 bet range for 1\3 here, especially with gutter + bdfd. Maybe check some AhTh hands. But most QX+ and gutter+ I would bet.

This is another one of the exploit spots where you can downbet to extract from a wider range and fold when they get crazy (I think the size is perfectly fine). We have to also realize that 98s get there. Sure he should probably c bet something like that but they miss c bets all the time. Turn is double gutted and river isn't all that scary for any combo of 98s.

Turn out I am over folding this spot :-(

RunItTw1ce u can see opponent hand even though u fold? ��

Hear somewhere - that we sometimes we have to bluffcatch the set, but i am not quite sure.

I am folding . It is hard to call without reads because like other said it is often flush . And i prefer bet bigger on river .