So, this is kind of an interesting issue that I've grappled with before myself.

The easy answer is that as the GM you have control over how much treasure your players find in your games. It's easy enough to just put in the amount of treasure you want them to find.

That said, one thing in OSR play that often gets overlooked is the idea of domains and home bases. Outside of actual name level domain play, investing in a home base or a local tavern or just in the local town is something that is extremely beneficial and also extremely costly to adventurers. There's a reason that so many older editions of RPGs included detailed information on exactly how much individual portions of castles or buildings cost.

Not every OSR game brings in the idea of domain play and strongholds, but I think they should. They're a great place for players to sink money while also gaining tangible benefits. And magic items also are subject to breakage just like other items. If your game is not breaking or wearing down items then maybe that's something you could look into tracking.

At the end of the day I think the idea of being showered in gold and treasure or being completely destitute and sort of fluctuating back and forth fits with OSR play because OSR play is just by nature a little more swingy. Life is cheap and death comes quick. Treasure follows that same paradigm.