Intersectionality is actually a cool concept. It shouldn't be the social media version of it, in which you tally up different segments of identity in order to see how many ways you are oppressed. I am thinking of it as intersection lines, or encrucijadas culturales. Hence my course on intersectional Lorca.
The original context, simplifying greatly: suppose a company hires white men to be executives, black men to be workers, and white women to be staff. They don't hire black women at all. But they aren't discriminating against black (since they hire black men) or against women (since they hire white women). We only see this as discrimination if we hold two ideas in our head at once, or the intersection between two kinds of discrimination.