Except why is there always an assumption that it is about his race? He dives, whinges to umpires and is a dirty player, so he gets booed initially. Then the media get on it and play the race card, Goodes does interviews and does nothing to dismiss this, which people dislike. The cycle then repeats with ducks and dives, boos are released, then more race cards played.
He has actually dismissed it in the past, and said he wasn't sure why they were booing. The media kept asking the question and added the racism element to the question, at which point Goodes had to address that particular aspect as part of the question, and it has snowballed from there.
The media frames these things and they take a life of their own, particularly with social media contributing to the agenda.