Watch an NFL game and then an NBA game. I would submit that there are dudes in the NFL who are every bit as tough as anyone in the NBA. Even so, the NFL tries to shine the spotlight away from those fellows. Instead, we see United Way commercials about a 350 pound defensive tackle planting flowers in The Hood.
Is some of this artificial? Perhaps. But, hello, is not most of entertainment artificial to a degree? News flash: When you watch a movie or a TV sitcom, those aren't real people. They are just actors who have memorized lines to craft a certain image. It is not real life. As such, if the NFL crafts an image of Kind And Gentle Giants, that is no more artificial than Superstar Recording Artists singing about how hard it is to struggle from paycheck to paycheck.
The NFL has done a GREAT job of crafting an image that appeals to everyone. The on-field play and occasional shenanigans satisfy The Bangers while none of the off-field presentation chases away The Scotch Neat Crowd.
The NBA buried itself. Even if they change their tune, I have been gone for 15 - 20 years and dont see myself coming back.