I think it was a matter of these guys living in an time where you were allowed to be more physically active, more physical, and take more risks. It wasn’t considered bad to grow real facial hair, have some muscles, and be a dude.
I think that it was also more attractive to be an adult and get some freedom than it is with 20 year olds today. Many of whom actually buy superhero under wear, spend all day playing video games, argue over comic book characters, and want to look more like an androgynous teenager.
Lifeless, spiritless, soulless. We all seen too many kids who are dead in the eyes.
They are told from early on that America is hell on earth and eventually they come to make it so, for themselves and often others.