Disapprove, but mainly b/c I dont find any action like kneeling, wearing a shirt, writing on their cleats or any passive "bringing attention to" act effective.
If you are a professional athlete, you have money and fame to actually do something about whatever you are "bringing attention to." Put your money and actions where your knee is and provide funds and actual effort to your cause. Anyone can virtue signal and then expect others to do the actual hard work. I'm not saying athletes may or may not contribute or donate, but I find it (especially now after kneeling has become sort of main stream) an easy way to make a little spectacle of yourself and then go back to your mansion to look at your Bentley collection.
But I also find the narrative hollow, painting America as this evil, racist country. Are we perfect, no? But in a nation of billions of people, it is impossible for everyone to be perfect, and be successful. But there you are, getting paid millions to catch/throw/run/punt a ball. If America was so horrible and racist, wouldn't we be watching some ginger named Bernie play your position. Take your knelling to North Korea or Saudi Arabia and do it during their anthems or prayer time and see what attention it gets you.