UTG(hero): $4064
MP : $1641
CO : $672
BU : $ 842
SB : $ 1571 (tabled started around him)
BB: $ 735

Pre Flop: (pot: $9.00) Hero has 7 7 5 5 2
Hero calls $6, MP raises to 27$, CO folds, BU calls $27, SB calls $ 24, BB calls $21, Hero calls $21

Flop: ($135, 5 players) A J 5
all checked

Turn: ($135, 5 players) 4
Hero bets $110, all folds except SB

River: ($355, 2 players) 6
SB checks, Hero bets $146, SB raises to $438, Hero ?

Turn i bet is if opponent has 23xxx, I still have odds to beat them since SB didnt raise me, I assume he doesnt have 23.

River i thin value to get maybe some 2 pairs etc and when he raises I am certain he doesnt have 23 or even sets so it is either nuts(which i am blocking) or nothing.

Maybe this is a bit too thin? I have been experimenting thin thin betting this few weeks trying to also make myself harder to play against.
Any advice where should I stop thin betting?

Fold pre or raise, we don't want to have a multiway pot with small pairs cause they flop sucker sets.

The fact that the game started around him says very little. Nobody is bad enough to overvalue a hand like two pair here and Wild players are generally cognizant of their image / won’t try to bluff you off of what looks to almost always be 32 or better. Maybe he’s a total drooler and you have info that would make this a call but most ‘catalysts’ are what they are in Omaha or Omaha 5 because they limp/call bad hands pre and stack off way too light not because they check/raise bluff rivers and blockers don’t change much, especially if he’s bad enough to raise a lower straight (which is I think a far more common mistake for bad players to make).

More info on what kind of fish SB is would be useful.
Preflop fold, this hand is really bad.
River you have one of the best bluff catchers, but people don't really cr bluff rivers in 5 card because blockers that can be duplicated are less relevant. I think you can safely fold, maybe show your 77 so he thinks you were bluffing

Fish are almost always (imo) more likely to show up with desperado bluffs that should never work than regs. That being said :

Fold pre.

Check the river.