while I too would be curious to try mech discs, to be honest, other than a few long mtns downhills (specifically with switchbacks that really did require frequent braking) I havent had issues with cantis. I do wish they were stronger for city and spirited driving at times, like V's, but do appreciate that they modulate better than Vs (which I find go from med to really hard braking quickly)
Ive put softer pads on my cantis over the winter and that should help, but over the years, Ive never had rim wear problems so all in all, non disk brakes just work well enough and are a known, simple technology that is rather inexpensive as well.

Coming also from a motorcycle background, I can see how hydraulic discs are probably very nice for their feel and modulation, but as others have stated, you get into the "simplicity" factor with cable brakes that is one less thing to worry about out in the world not near a bike shop.