Suppose you started each work day with a short protest. You believe with all of your heart that everyone should get a free donut on Friday. What if, in the course of your protest, customers are visiting the plant where you are employed? Instead of workers diligently producing high-quality widgets, they see workers protesting? Would your employer have the right and obligation to tell you to knock it off, even if your quest for donuts is laudable? Even if a majority of Americans would agree that free donuts would be awesome and could we get bacon too?
I'm pretty sure your employer would have no issue with you protesting on your own time. It is doing it on company time that is the problem. You might counter that if you can carry out your campaign at home, no one besides the wife and kids, the dog, and a few neighbors will notice. At the factory you can proclaim your agenda to six hundred people who might then start their own protest.
Yes and don't do it on company time. Period EOD.
Scenario two: I show up at a cutomer's location to sell him widgets. Instead of business clothes I wear a sweaty T-shirt, a faded cubs hat, and the grass-stained running shoes I last wore to mow the lawn. Would the boss have the right and obligation to tell me such behavior is unacceptable? Should he fire me?
Can the NFL tell players to protest on their own time? As owners of the business: yes. It isn't about right or wrong. It certainly isn't about Constitutional Rights to speech. I don't have the right to tell my customers I am peddling semi-junk Chinese widgets, even if it might be true (it's not), and you have no "right" to argue for free delicious awesome donuts on company time.
Oh, and Kareem Abdul-Jabbar can complain to the owners of he NFL all he wants about not wanting protests on company time. It does make him a hypocrite when he has no issue with the fact that the NBA, you know, the employer who paid him millions, has had the same "You will respect the National Anthem" policy for decades. It just makes his editorializing reek of opportunism.
If the NFL owners are Ok with protest, fine. If not, equally fine. it is their business. The consumers will vote with their wallet and viewership if they agree or not.
I am all for justice. I long for a color-blind society. But sometimes, I just want to watch football. I do not think I'm an anomaly. That position does not make me a racist, nor does it mean I condone...well, anything. It means I want to watch football without interference from a political agenda. No more, no less.