There is no right to free speech in a private enterprise.
Are you saying that any business can suspend the First Amendment? They can certainly fire you for disruptive behavior but you still have a right to speak if you choose to risk your job. And I support that view as the rest of my post makes clear.
But.... I if any player in black magic marker wrote MAGA on his shoes, they would NOT allow him his right to free speech. Only Black Lives Matter and PC stuff. THE NFL Commissioners are totally biased. No real honest effort here to play games of sports, but to push their social agenda. Moving OUT of the knot hole zone.