I think you are correct on 90 pct of people. I think there are some outliers - people with particularly long thin faces or very round faces where it might matter. However, I am firmly convinced that long necks need a longer higher collar (that's me). I didn't really get the collar thing until I started buying bespoke shirts and was fitted by someone who really knows his shirts.I honestly have never understood the notion of wearing a particular collar if one has a particular shape to his face or a beard. A medium spread collar, I argue, looks good >90% of the time.