We are going to start veering away from on the field football discussion, but IMO it's possible to be an activist and a football player and not be disruptive. If CK had kept those two separate, he never would have found himself in his current situation.
Not sure why he couldn't have done everything quietly football related and start a separate foundation, program, or cause for his off-field social issues or concerns. In this day and age, there is so much coverage on-line or through social media, he could still have gotten a ton of exposure for whatever he wanted to get people in front of in terms of social injustices. But then he wouldn't have been able to play the victim or martyr card.
He essentially has become an activist that was once a football player, not a football player that is an activist. Personally, I am not even sure he is truly an activist, as it seems like he has looked to cash in on his causes and has been paid handsomely by Nike along the way. Whether an activist should be looking to or able to cash in is likely a different discussion.
As far as his "football abilities" go, that's something else where "beauty is in the eye of the beholder." As I have alluded to already in this thread, if Kaep all along wanted to: be a starter and get $20+ million a year, would not seriously entertain a back up role, and likely refused to take back up money, then he sort of made his own bed and has to lie in it. However, that further stokes the fire, spin, and narrative that he "sacrificed and stood up for a cause." To be clear, that is not a jab at people standing up for a cause, but it is a dig at CK for trying to play himself to be the aggrieved party when all of this could have been avoided if he went the more traditional route that unemployed quarterbacks take (accepting less money to get a short term contract, earn back a starting role, and then try to get a bigger starter's deal).