There are different points of view - I get that. Pop calling anyone who disagrees with him "ignorant" is in itself an ignorant thing for him to do. It's a long way from "This is what I believe" to that kind of rhetoric. Name calling in that cir stance is a pretty stupid choice for someone who believes he is so wise. He's as guilty of fanning the flames as anyone else.
And, no, Kaepernick didn't "sacrifice his career" with the kneeling protest. He sacrificed his career by being an ineffective quarterback. Pop wants to perpetuate the idea that this is the 60's and Kapernick's protest was the equivalent of the Selma march, and that the mean ol' NFL kicked him out of his career. But the fact is, he played a whole NFL season after he first took a knee, and had a QB RTG under 50 and his team was 1-10 with him as a starter. The year before they were 2-6 with him as a starter, and he had a QB RTG of 43.
The "sacrifice" narrative is a myth that helps a certain type of person with their white guilt, but it totally ignores the fact that Kaepernick was on his way out before he ever took a knee, and his play in 2016 was the coup de gras. I don't give a if he wants to protest, but he played himself out of a job. He would have done well to focus on getting better, just like Pop would do well to focus on getting this thin team ready instead of holding up the ghost of Colin Kaepernick as "proof" of the boogey-man.