what is recommended play vs people that do not bluff the river much at all?
do we just fold more vs their valuebets on the river and that is the end of it or do we change our strategy on the flop & turn so that we have less bluffcatchers?

On the river when OOP, Fold more, but accomplish this by moving your combos on the river down in your ranges. So, some combos of bet-call become bet-fold, some combos of bet-fold become check-call, and some combos that were check-call become check folds.

In position, highly polarize your range favoring check over bet. Only call donk bets with top value. No bet-calls (other than nuts), and only bet top value and balance these with enough busted draws to be non-exploitable.

On the flop and turn, it is not so simple. Stay balanced as much as possible on these streets, and when it is heads up you win more by doing so.

This doesn't make sense. Why would we start check/calling hands which could be bet/folds against someone who's unlikely to bluff? The other parts seem correct.

No, we can value bet thinner against someone who doesn't have river bluffs because they realize their SDV more often.

On the flop and turn we can continue more often with bluffcatchers and value bet weaker hands than normal, expecting to be able to show down against more of his range.

My main adjustments would be to never check/call or check/raise the river. Any hand good enough to show down to a bet against a passive player is good enough to value bet. Our best hands have little incentive to check/raise. Check/fold hands that are too weak to value bet, bet/fold everything that can be value bet with a balanced range of bluffs. Value bet the river thinner IP, too.

Like I said before, call more bluffcatchers on flop/turn knowing that your opponent will let you showdown on the river, assuming they are still bluffing at "correct" frequencies on earlier streets.

I'm a couple beers deep and only skimmed the thread, but the distinction between facing a river range that is value heavy on the turn, and a river range that is not value heavy on the turn, is an important distinction.

Yep, I think ^that^ is right.

If villain isn't bluffing the river at near-optimal frequencies, you shouldn't be calling with any bluffcatchers, since they won't break even against an unbalanced value-heavy range. You should only call with hands that beat his value range often enough to break even at whatevever pot odds are laid. e.g. If he pots it, but always with made hands and no air, everything you call with needs to beat a third of those "value" hands.

I'm not sure about the earlier streets, as OP didn't say anything about villain's tendencies there. If hero is in position, he should be able to float the turn very wide, because unless villain somehow has a ton of value hands, he's gonna check-fold the river a lot, isn't he?

It depends on how thinly they value bet the river. Against a player who never bluffs, but makes stupid value bets that have no chance of being called by a worse hand, then you should check/call more often if bets hands that he would fold if you bet.

You should consider folding some hands on earlier streets that rely on implied odds since you won't get value from bluffs. You might still get enough value from when he hits and you hit, but you might not want to chase something like a small flush draw because your opponent won't try to bluff a river scare card when the flush comes in. It depends on your opponent tendencies, as usual. If he still calls too much with non-flushes, then you might get enough value when you do hit to draw to your flush.