So here's a personal perspective. I had Colin Kaepernick on my fantasy team. I picked him up on waiver in 2012 after Alex Smith, the starter that year, had a concussion. Then I pick him up again in 2013 when he lead them to a NFC Championship game. To me his decline happen after the fine for using inappropriate language on the field. Then the fined for wearing headphones to a press conference. Then when the new coach arrived in 2015 he was playing like he wasn't familiar with the game.and was replaced mid-season. Then there was injuries, the weight loss, the hair style, and the infamous "National Anthem Kneel". Which launched the most profound awareness campaign about social injustice and police brutality. In my opinion Colin Kaepernick didn't make any alliances in his protest.
When you are engaged in disagreement you have to provide a solution and a way out. Kaepernick provide a sound campaign with no resolution or end game. Yes it's difficult to swallow but if you allow the perpetrator to provide the resolution you will never get what you actual want. Remember, until Kaepernick brought up the issue, the NFL didn't know there was a problem therefore how can they possibly solve it.
Should he play. I am under the belief that he has nothing left to offer the NFL as a player. Let me offer clarity Colin Kaepernick could give us one miracle season that will leave us in awe but nothing long term that a team could build on. That is the disappointing reality of the Colin Kaepernick story.