White Jazz fans, not wanting the assertions to be true, are much more likely to give the fan the benefit of the doubt as to what he said than people of color or fans of other teams. That’s the part where I think many white / BYU / LDS people have a blind spot. We don’t like the negative implications of a particular narrative so we view uncertain events with our own confirmation bias.
I don’t know what this guy actually said. I don’t know whether his alleged tweets are real or fakes. But stepping aside from this situation, I do believe that there are those inside the Church, at BYU and within some of our own families who hold and even publicly espouse racist views. They may not be many, but If we want to have an impact on a narrative we find to be wrong or feel is unfair, then we need to be vigilant in opposing that kind of thing whenever and wherever it appears.
I actually have faith that if someone on the sideline in the Viv said things that the surrounding fans considered racist that there would be plenty of Jazz fans that would speak up. I hope that is what would happen.
EDIT: The OP did acknowledge that the confirmation bias goes both ways. I didn’t acknowledge that in my original post.