Why Boo at taking the knee?

COVID-19 restrictions were lifted and for the first time in months, people were allowed back into stadiums to watch live sport. Fans bring energy and a dynamic to the game which is contagious to the players and fellow supporters alike. This dynamic is perhaps never better demonstrated than with football. Fans can bring support, camaraderie, positivity, hope, and belief that “our” team will prevail because we are “great” we are the “best.” There is nothing wrong with this. It is natural to cheer on your team. We, humans, are, after all, tribal by nature. However, sports fans are not a breed apart, they are made up of a cross-section of society with all the baggage that our modern society brings. That being said, it was still deeply troubling that a number of Millwall supporters were heard booing the players as they bent the knee before the game.

I felt angry when I saw this. I also felt saddened. However, my main reaction was confusion. I was genuinely puzzled as to why. Was it just a knee jerk (no pun intended) reaction? We Millwall fans are “hard men” and we don’t give a toss.  You do get the occasional rebels who will boo during various "minutes silences" in respect of an anniversary or remembrance.

Did they think the gesture too politically correct or “Woke” as seems to be the in-vogue word?  Judging by comments posted on message boards such as “Well done Millwall lads. Only club with the cohonas to sound out this left-wing claptrap”. And “Well done Millwall, enough of this claptrap posturing.” this would seem to be at least part of the reason. However, the crowd reaction came despite Millwall manager Gary Rowett and his players releasing a statement ahead of the game in support of the movement.
It read: "We are fully supportive of the efforts in ridding the sport, and society, of all forms of discrimination. It is our duty to reinforce positive messaging. Taking the knee, for us, is in no way representative of any agreement with political messaging or ideology”.

"It is purely about tackling discrimination.”
So, can we assume then that those Millwall fans who booed are not in favour of tackling discrimination?

Or was the reaction just another example of blatant racism?