To your point though, if the only racism/sexism/bigotry is in my head due to some sort of white/straight guilt, then I should probably be quiet. Overcompensation is a thing, particularly for people raised in questionable environments or not used to being in, shall we say, mixed company. I moved from middle Tennessee to Baltimore, MD when I was in my 20s. My first job was at a call center where I was a minority. It was strange, but a good growth experience. Realizing that you can talk about race without being racist, that you can notice that someone is black...its funny to look back and think about how sensitive I was to these things.
From the outside having knee jerk reactions and assuming racism is a mistake. Getting offended on someone's behalf is usually a mistake, though sometimes things are too blatant to ignore. When someone tells you they are being attacked or treated unfairly, you should consider it. It doesn't mean you will agree in the end, but just dismissing it is a mistake.
"White people are the oppressors" is statistically and historically accurate simply based on the numbers and who is in the majority in the US. However, it isn't a useful metric. Its like saying 'since rapists are men'. So white people being necessary to overcome racism is true due to numbers, not because of whiteness.
I refuse to form tribal lines based on sex, orientation, race, or religion. I have my family and my country as two examples of tribal lines I recognize. But just because I don't form those lines myself, doesn't make me blind to the fact that others do, often unconsciously. Seeing BLM calling out cops as an attack on all white people. Seeing PRIDE as an attack on straightness and as some soft of 'gay agenda'.
If my gay friend is being bullied or even just being made fun of, am I a 'straight savior' for calling out that asshole? If some guy tries to roofie a girl, am I being a male savior for saying something? I say, no, that's just doing the right thing. Injustice against a fellow American is not to be accepted.
People deserve to be judged as individuals, so when black crime statistics are brought up, or things like 'black on black' crime are used to somehow justify a white person treating a black person differently, its something that has to be called out. "if they don't care about black lives why should we?" ignores the fact that an individual black person isn't a statistic.