Of course it does. Itās their Constitutional right to protest the government by not standing for the National Anthem. Thatās what our armed forces fight to defend. So why do you hate the Constitution?
Whether someone agrees with the basis for the NFL protestors does not have anything to do with the Constitution. Very few people, if any, have claimed that the players do not have a legal right to protest. Instead, those who are boycotting and angry about the protests seem to be saying they think it is the wrong way to go about it, the wrong venue, or a false narrative; things of that nature.
I tend to see the outrage over the few protesting players as a sign of extremely questionable standards: boycott over peaceful protests, but not over the various cheaters, drug users, and criminals in the NFL? I don't think it speaks well of a person to get so upset by a protest about racial inequality that one has to boycott, but not bat an eye when a convicted dog ring runner gets to come back after prison to be a starter, or a player like Pacman Jones, who has been arrested seemingly a dozen times, and even was drafted while on probation.
That said, trying to make this out to be a Constitutional issue is disingenuous at best. Players have the right to protest, as do all US citizens. That does not mean that anyone has to watch, nor does it mean that deciding not to watch is in any way a violation of the players' Constitutional rights or a wish for the players to be denied those rights. Having a right to protest in no way requires others to accept the validity of the protestors' opinions or message.
The KKK has the Constitutional right to gather and protest, let's say school integration. Does that mean if you denounce the KKK and their protest, that you hate the Constitution? Of course not.
And just to make a quick comment about whether players could be suspended for the protests, I think the NFL would have a pretty good argument that they can be, based on the relevant portion of the NFL Game Operations Manual. They don't appear to be following that path, though. Perhaps after the season standing during the anthem will become mandatory, who knows?