It sounds like she's both socially and fiscally liberal, but doesn't identify with the mechanisms at play in the liberal sphere because they threaten individuals. In many states in the US, socially liberal policies like abortion, gay rights, etc, etc are heavily blocked and contested, so I don't agree with your characterization of these as mainstream. I agree they are mainstream among liberal Americans.

My understanding is that her article is advocating for respectful and open discourse, and greater detail and understanding of the issues is always welcome. The point I see is that a person can be offended by a post or statement, out of context of the post's intent. Currently, the discourse supports the offended person, and condemns the poster. For example, in the gentrification example, the retweet was focused on communicating relative wealth of the communities, it was not focused on the political issue of gentrification. The author was not saying she agreed with gentrification, and was expressing any opinions about race, rather, she was trying to communicate the relative wealth of the different communities. This backlash to her retweet drove her to release an apology.