Which means, at a baseline, if you're in the majority you're an oppressor.
I wouldn't go this far, although I'm sure some people would. At the end of the day, being a white heterosexual male means that you are likely to experience advantages compared to people who don't fit into one (or any) of those categories. That doesn't mean that you should spend every second of every day trying to atone for that privilege, but that you should try to be aware of your position relative to others. Nor does it mean that any hardship you experience is insignificant or should be ignored because of your (relatively) privileged position. People who try to convince you otherwise are just narcissistic assholes, regardless of their ethnicity/gender/orientation.