Reid being brought back into the league shows you that teams are ok with some of that off the field stuff.
But again, Reid isn’t the lightning rod Kaep is and, even more than that, an NFL team deemed his talent to be worth more than his distractions.
Maybe someone will do the same for Kaep but Reid is probably a better safety than Kaep is a QB.
After thinking about this a little bit, I think that the threshold for acceptable distraction is much higher for Reid, a safety, than it is for Kaep, a QB. My guess (based on pretty much nothing other than gut feeling) is either there is no acceptable amount of political/social activism distraction that teams are willing to take on for a QB, or that he would have had to been Russell Wilson/Lamar Jackson circa 2019 for multiple straight seasons in order for teams not to care. I believe that, given the blue-collar nature of football fandom and the fact that Kaepernick's viewpoints were hugely at odds with said fan base, having Kaepernick play the most prominent position on the field had the potential to seriously affect the NFL's financials.
So in a sense, yes, he's not good enough, but I don't know if anyone would be good enough. Kaepernick at his best was probably around top-1/3, so he was nowhere near the very high threshold likely required for the NFL to be willing to put him out there despite his activism.
Also, the fact that Kaepernick is coming off as combative about this whole ordeal is likely to rub a bunch of alpha male billionaires the wrong way. I'm sure he's aware of that, which leads me to the conclusion that his activism is more important to him than his football career. That's fine and is his prerogative, but he's certainly not making it easier for teams to hire him.