"Marginalized person: Any woman who wants to work for pay for an employer"
"Oppression: The self-reinforcing system of stories, TV, news coverage, police, and legal system stereotyping Black people as criminals, that benefits non-Black people and harms Black people"
What TV shows has the author been watching? For my entire life, at least 95% of the depictions of black people that I've seen on television have been positive, sometimes to the point of being pandering. (For example, if a show has a black character and a white character, and one has to do something wrong to advance the plot, it will be the white character, because that won't cause outrage, while the reverse will.)
"You are eating lunch in the employee kitchen when a group sits down near you. One person comments loudly “If I ate that, I’d be as big as a house!” A higher-weight coworker is sitting nearby and can clearly overhear."
It's not clear who's talking to whom here. If it's someone commenting on the lunch of a coworker with whom they're not sitting, well, I've never seen behavior like that in any workplace, nor have I heard of anything like that happening. If it's someone commenting on one of their lunch-mates' lunches, then it's none of the "higher"-weight coworker's business.
"Higher weight people face workplace discrimination, particularly women, regardless of ability to do the job Body size is falsely equated with virtue: self-control, hard worker, in good health"
Body size is correctly associated with self-control, energy, and good health. The proportion of overweight people who couldn't reach a normal weight if they ate sensibly and exercised is tiny. The "healthy at any weight" meme is absurd.
"Black people face a much a higher bar than white people during hiring (and in general), and white people often get a pass or exceptions to the process"
Bullshit.
"A co-worker shares an article on your work Slack claiming that white men are biologically more suited to STEM careers, saying "I don't agree with all of it, but it has some good points." Another co-worker replies, saying that they disagree with the article but we have to be tolerant of co-workers with different political views because diversity of thought is important too."
Men are biologically more suited to STEM careers, on average. You have to be willfully blind not to see that this is true. Why does this make people so angry?
""Office housework" is necessary but unrewarded work (taking notes, organizing parties, tidying, etc.) People of color and women of all races are expected to do more of this work and punished for not doing it"
Bullshit.
"On a company mailing list, someone writes “How would you explain this [technical thing] to your grandmother?”"
Old women (and, to a lesser extent, old men) are much more likely to have trouble with technology than are young men (and, to a lesser extent, young women). Again, why does this make people so angry?
Intersectionalism is just borderline personality disorder in ideological form.