At 11th level as a party of five in an Ancient Greece theme game we have about 15K between us not including another 1K worth of diamonds for material components. Or we did until we came across the king of a city-state whom had a treasury with magic items he was willing to part with for coin, and now we have like 400 gold.
That's not really a low gold game, we just spent it on thing in-game, from bribes to outfitting a stronghold to feeding a neighborhood and generating goodwill. You know, all the stuff that people who say "there's nothing to spend money on" completely ignore because what they are really saying is "3.x and 4e had magic items as part of the character advancement mathematics so had a magic item economy and I have been trained that gold only has value if it directly adds to my character sheet by those editions", but often don't know that's what they are saying.
In Avernus there was precious little material treasure, so we had next to nothing once we went there. That went up to 13th.
In CoS, until we just hit the big treasure room in Castle Ravenloft one session befgore the end we were having problems buying mundane equipment at 8th. But that's also rather campaign dependent.
In a completed campaign, 1-7, we went between riches and poor many times, as we got rewards and then spent it. I think 5000gp was the most, but at like 4-5th level that's a good deal.