The only problem with wait your turn (I find) is that it does not exist with most surfers. I surf and sup but I hardly ever hear surfers say "you go, you were here before me ". Its more like paddle (snake) to the shoulder and take priority.
The only people I ever hear "you take it" are some of the sup crew. Probably because we know we will have good waves every surf.
It is daunting when surfing if a couple of sups join the peak as you know that even if they take turns you are down the pecking order but then again its the same if a long boarder sits just outside you in the line up.
On my sup I try where possible to surf a peak away from the surfers. A few weeks ago I did this and had some good waves, 3 surfers see some of the waves and paddle down to the peak I'm on, then, complain that I took the set wave as went down the line and they had to pull off. F*****g sups as I went past. I ever so politely told them that I came to this empty peak not to intrude on the surfers already in the water on the 3 mile beach. I then politely suggested that they move to a peak further down
Problem is that some (not too many where Im from) sups do have the every wave mentality and some surfers think they own the waves.
I dont think this problem will ever go away.
Not until everyone has respect.