All the men from teens to elders looked like gym models. It never struck me until I was in my 30's - but really I have the body of a sick individual and the guy on the gym adverts is actually what the human body looks by design, not some sort of aspirational dream.
I've seen comments like this before, and they're valid, but I've also seen evolutionary biologists and/or anthropologists point out too that many if not most people who are wounded or sick die. So you're also seeing selection bias, where the healthy thrive and you don't see the unhealthy because they're dead.