Villain's 43/22/1.94. Is it possible he folded a J here? I figured he could have T9, Jx. And he doesn't strike to me as an intelligent player. I figured this play has more value if he calls with those hands - checking and letting him bluff with a missed draw might work too, but meh.

Also his river agg is 0.6

this is not a good river play imo.
i would bet something like $40 to try and make it look like a blockbet/scared value bet. if he is aggressive, he could try and represent that Jack and bluff on you. if he has the Jack and has at least a decent kicker, he will probably raise it. and he might do some hero calls with like TT, A8, ...

as played he prolly will only call with a strong Jack (like AJ/KJ) and the straight unless you have been abusing him recently with raises and reraises.

Aight, I did mention his river aggression which was very low. And I did c/r->c-bet turn as semibluff before and forced him to lay down a goodish hand (at least that's what he said he had). c/r:ing probably has most merits in this case though.

quit trying to be fancy and just bet the goddamn hand.