i was lucky to be born that way, I just got a bit bigger.
Oh, and whatever people say about people not training for proportion, I always have, my legs overshadowed my upper boy, i trained to make them balance.
I was always obsessed with proportion/balance (not size ) ,that's why I train my triceps once a month and my biceps twice a week , calves 3 times a week,  quads once a week .............. .
I'm a firm believer  that while you can't  change your muscle bellies , insertions points ........etc ,   you still can make your body proportionate
I don't know how much these guys weight but all of them have classic physique , why ?  because the  judging criteria was different