In the beginning of the 20th century, it was relatively easy to be a professional football player. If you were there, you were able to run at someone and hit them, and you were able to take those same hits, you had a pretty good shot at making whatever local pro team. Sure, the bigger, faster, and stronger you were, the better your chances, but the minimum athletic bar to become a professional athlete was not that high.
As the years go on and as the stakes climbed higher, the level of athleticism climbed along with them. No longer were Super Bowl quarterbacks working nails during halftime. Not only did the actual conditioning of athletes get better, but so did the pure athletic talent of said athletes. Compare the “athlete” of yesteryear with the walking (running, jumping) Greek gods that currently ply their trade in The National Football League.
Within the current framework and rules of American professional football, certain traits are selected for. Just having the desire to hit, the tolerance to be hit, and the willingness to drop your factory job for a couple of weeks a year was no longer enough. You had to win the genetic lottery and be a physical and mental specimen of such rarity that one might scarcely believe you share the same genus as some your lesser fellow humans.
This also means that other, non-essential-to-football traits are disregarded. Does it really matter if an NFL-level talent is also a supertaster? Does it really matter if an NFL-level talent enjoys foreign films? Does it really matter if an NFL-level talent is a conscientious father or husband? Fuck no. But, of course, they are still of such rare quality, their relative weaknesses in other non-essential-to-football traits are hardly detriments to their career prospects.
Those who can truly affect the world of pro football are of such rarity, that these weaknesses don’t, in the end, matter. Now, that is not saying that these failings don’t mean anything, just that they don’t mean anything in the highly-specialized, highly-competitive realm of football. You can have a terrible palette and still be a pro football player, you can be cultural philistine and still be a pro football player, and you can be a mediocre human being and still be a pro football player.