It's one employee who's prioritizing minorities. I'm not an HR or legal expert, I don't know where that employee's statements fall with regards to equal opportunity laws. They might be fine, they might pose a legal problem.
I have trouble believing that the intent of the post on HN isn't to just stir up controversy and spark a argument between incels and sjws.
Things I need more in my life: feminism, comedy, truth, and less Black people [..] I also care deeply about equity in hiring. Therefore, I choose to prioritize folks in our white communities
Because whites are underrepresented at Dropbox in all categories except leadership (where they are 58%, exactly their current share of US population): https://blog.dropbox.com/topics/company/our-2021-diversity-r... (scroll to the very bottom for the chart: https://aem.dropbox.com/cms/content/dam/dropbox/blog/company...)
Given the comment history of OP, I would be inclined to agree.
She's a racist and she represents the company as their hiring manager. They read her tweets and approve of them, and are thus liable for her actions.
These are not her personal opinions - she states that they form the basis of her choices re who gets hired.