Although some would see this as a very selfless act of regard to the nation but the president had an opposite view you could deduct from his tweet that he was attributing the flaws of the league in some areas to the humble actions of the player.....
I would kind of think that having run an NFL team and being POTUS he should be entitled to voice an opinion. Particularly since he's the guy that has taken action for criminal justice reform, and inner city ghetto improvements.
Personally I don't watch the football games but found those acts of defiance extremely offensive. I also thought they were very poorly defined acts, as they could mean any and everything to someone.
As opposed to holding a sign stating one's view on a matter.
A poorly defined act of defiance is really worse than no defiance at all, particularly after our media friends get ahold of it and twist it around.