A2s 3bet pot IPP

I prefer 4-bet bluff A2-A5s instead of calling those in these positions.

I think I would 4b bluff here as well.
As played, we fold river indeed.

4b bluff is ok.
But the disaster is on flop. Not calling here.

Flop call is fine with gutshot, overcard and backdoor flush draw. Turn is also a call.

River depends on your reads but vs unknown i would most probably fold.

I would bluff 4bet this, don't see any reason to call with this hand.
OTF is a fold, in reality backdoor FD and gutshot are quite bad. OTT is a clear fold too, our kicker is bad and we can't river a flush.

4bet bluff this hand all day.

That being said if this is going to be in your 3bet calling range, you really can't fold on a flop where you flop a gutshot.

Calling flop is no disaster. It is floating with overcard, backdoor, gutshot and position. It is mandatory if you call preflop with this holding.