"If you reward the right guys, then everyone would be training to have a beautiful body again...." This in contrast to having bodybuilders with distended stomachs winning shows etc.
I'd take it a step further by saying that you, (as a competing bodybuilder) will be penalised if you come in under 10% body fat on the day of the competition! By doing that, I would achieve one extremely crucial element, whilst the other leaning more towards looks etc.
The first and most important factor, the one relating to the body fat percentage would serve to ensure a better health and wellbeing of that competitive bodybuilder,which ought to be paramount above and beyond any other element in our sport. Mohammad Benaziza (the giant killer of the 80s) collapsed and died after winning and beating Lee Haney in one of the grand prix, due to diuretics...all in the name of looking super dry with paper thin vascular looking skin. At 10% body fat (a place I've been before), would allow the bodybuilder to have all the striation he wants, without plunging him into the danger zone, a zone requiring not just some great effort in the gym and outside it, but also requiring the resorting to some fat burning drugs etc.
There was nothing wrong with the 70s and early 80s look of a bodybuilder.
And if some of you say yeh, but those bodybuilders had less than 10% body fat, my reply to you would be to have a bodybuilder's look that belongs somewhere post competition look, where muscles are fuller looking, adding to the massiveness of that bodybuilder in question, rather than one with an emaciated looking face resembling some starvation concentration camp of some sort!