One, I didn't see any non-black players kneeling. I did see white players standing with their hands on the shoulders of kneeling black players as a show of support.
Two, if you don't see this as a dog whistle the racist right is blowing, then you are the one who is lost. The attitude of trump, hannity et al is "those ungrateful SOBs who are millionaires should be thankful to be paid exorbitantly to play a game in this country." And the poor white people, their base, eat it up.