Upper Green River

Waded a couple spots on the upper Green recently, between the dam and Greensburg. Stream looks great for smallies and other warm water fish: good flow, structure, clean water. Yet I found relatively few fish, compared to a stream like the Elkhorn, and am wondering why. I was fishing at some popular access points and it's possible the fish get pounded pretty hard there. Maybe well downstream or upstream of these spots would yield better action. Also wondering if dissolved oxygen in the stream could be an issue. Water temp has been 80 degrees recently, and if it's coming from the bottom of the Green River Dam, it's possible it can't hold enough oxygen at this time of year. Just wondering why a stream that looks so good seems to have so few fish.