The problem with 'taking the knee' is that (1) it has been going on for too long, and (2) it only seems to be applied to football. Why don't all sports do it? I don't recall any rugby players doing it, and I certainly didn't see any tennis players at Wimbledon either. Nor golf, or motor racing, darts, snooker, or any other sport you can mention. Why only football? Do they think all fans are all low-life racists who need educating?
Like the public in general, the vast majority of football fans are not racist, and they are starting to resent being told that they are, every time a game kicks off. That's why people boo - not because they're racist, but because they're tired of being labelled as such.