Well, from my (probably lot longer) experience, I don't think it's four wheel disc brakes that's the common factor. All the cars I've owned, back from the late 70's (incl. Alfa AlfaSud, VW GTI, Honda Civic Si, Audi 4000/90/A4/A6, Honda Odyssey, Pontiac Solstice GXP, etc.), have had 4-wheel disc brakes. All of them up until our 2014 Mazda have worn the rear brakes far less than the fronts. In fact usually I averaged 2 fronts changes to only one rear change
I was really surprised to find that our older CX-5 had worn the rear brakes down to nothing while the fronts were still good. I assume that will hold for our 2019 too, when we have enough miles on it.