Since when is it acceptable for professional athletes to call others female genatalia as an insult?

Pretty sure if Lebron James and Steph Curry constantly called each other "pussies" it would not go over well with the leaders in their league and the fans in their sport.

How about if Peyton Manning threatened to "kill" Tom Brady....literally kill him.

Would Rory McIlroy lose sponsorships or get fined for telling Jordan Spieth to "suck his dick"?

Just curious why this type of behavior seems acceptable in mma....