Restrict outfitter/guides who have positioned themselves to make some money taking other people out fishing? But if it was the same number of friends fishing the same water, that would be acceptable? Not sure I see any difference except that the guides are being painted as a boogieman. I use a boat to float the same stretches and have a lower impact than having somebody else do the rowing? That could work I suppose since I can't run the boat and fish at the same time. So maybe the answer is no more than one person per boat.
Using a guide allows you more to time to actively fish the river, reducing the time and subsequent pressure in any one area as well as contributing to a more enjoyable day since he knows the poor spots and problem areas to avoid. As well, a new(ish) fisherman can be supervised/advised on fish handling by the guide. I've taken new guys out and their practices can be horrifying. Besides the fact the guide will try to keep you legal.
I look forward to my guided floats because it's just a much more enjoyable day, aside from the fishing. When I drive along the upper Missouri and see all the nice water that I can't access without a boat it's frustrating. But I could fish the easily and publicly accessible areas to my heart's (dis)content, same as any stream here at home.
Maybe the answer is to make classified waters, restricting the number of rod days and perhaps even breaking it down into stretches that you are allocated for your day if the intent is to reduce the pressure for any waters that have gone downhill. Hands up: who wants to go down that road? And unenforceable without more CO's on the "ground". It's only fair that their pay, benefits and resource requirements are paid for by the people that they're watching, not general revenues. If you walk and wade, maybe a better situation than now. If you have a boat: do you look forward to only being able to use it a few days a year? If you're lucky at drawing lottery style permits. Go that way and you'll undoubtedly have fewer guides on any given day, with prices that put such a trip into the realm of "for the well to do only".