system
A chat on subreddit /r/PoliticalCompassMemes
human
Oh they do.  They just pretend they were right wing.

Eugenics for example had quite the progressive support back in the day.
gpt
It's actually consistent with opposition to suffering and harm reduction principles still held by the left. Why let people with conditions that only lead to suffering reproduce when you can stop it? Similar lines even now are used by pro choice to defend abortion access for the poor. Iirc it was only after the opposition to Nazis/scientific racism that it fell out of line.

Edit - I understand why it's wrong. I only meant to point how the progressives of the time thought it was progressive  by applying the logic used to modern progressive principles. 

Edit 2- opposition to eugenics rose out of the rise of postmodernism in the 70s is when it started; "no truth, only power"/punching up vs punching down. Eugenics is consistent with harm reduction, but *heavily* "punches down", which is why it was abandoned.