this nihilistic misanthropic forum, where most people disagree with genocide.
Out of curiosity, where you get this consensus? Eugenics is more properly philanthropic by the way, especially looking at the word's etymology.
People over 120 leads production, people under 120 produces.
This was addressed earlier.
If the idea can be agreed upon as good (the idea being that eugenics in some form or another is good for the human race), then the methods and precise scope can be addressed later. Anyways, this can all start on things most people would agree upon, such as more capital punishment in murder and rape cases, as well as immigration reduction to the First World (or cessation ideally). If these are addressed, moving forward in anyway on this issue will be alot easier. Whether or not the "kill everyone under the IQ of 120" statement is rhetoric or not, eugenics would be beneficial in the long run, and not tolerating weakness (especially where it will breed longterm parasitism) is a good principle to live by.
I also believe people forget that in the early 20th century, there was a movement in the US that gained significant approval and national momentum to institute eugenics, as far as limiting immigration, and sterilizing people went. Though it was obviously fought and lost, there's possibility for it to happen again.