How is race different from other social constructs? Aren't they all made-up ideas that don't exist in nature? Yet if you challenge work hierarchies, gender norms, marriage, acudemia, etc, you'll quickly run into trouble. How is race different?

No one is talking about you. I have no idea how you vote or how you were raised, and that doesn't matter. Racism is not an individual matter; it's a systemic matter. To some, it's a bug in the system; to others, it's a feature.