They want you to work hard, they want you to succeed, and they want the sports to grow. But these governing bodies of all sports have to look out for the public view and the perception of injury. 100 years ago there were deaths and catastrophic injuries to football players, so they made changes, added pads/helmets/more rules to enhance the way the game was played and viewed. NASCAR as you mentioned earlier has its own rules for the safety of the particpants, yes they go over 200 mph, but those cars are limited on what they can do to maintain participant safety and overall public satisfaction of how safe the sport is. And now in recent years with the NFL changes, NBA foul rules, redefining of NCAA rules for multiple sports, they are limiting the players for safety to allow these activities to continue. Tom Brady is allowed to throw as many touchdowns as he wants, but the defensive players aren't allowed to tackle as hard as they physically can. Which seems unfair to them right? But paralyzed quarterbacks across the NFL would ruin the sport. Precautions must be made by governing bodies based strictly on data and feedback from the athletes and the public.