Hmm. I was curious and decided to google that, and found this:
https://www.housingisahumanright.org/what-is-a-yimby-hint-it...:
> To sum it up, YIMBYs started with a self-serving agenda: to force the production of more luxury housing that they could live in — no matter the consequences to working-class communities. To further their agenda, YIMBYs co-op housing justice messaging, but they’re not housing justice activists. In fact, they have a long, disturbing history of clashing with the housing justice movement. YIMBYs push pro-gentrification, trickle-down housing policies that generate obscene profits for Big Real Estate — and they’ve continually ignored the negative impacts of their policies on working-class residents. YIMBYs are not going away if politicians continue to support them. YIMBYs, put simply, are bad news.