Ok so that dude says that musk did positive things (which is debatable but that’s not the point). People vote him down and he is pissed of by this. So he brings that ppl will downvote him, because people generally dislike Elon Musk anyway.

As Germany had to deal with the Nazis a lot of people were subjected to massive propaganda as the Nazis basically controlled all the public information sphere. So what happened was that many/some people read in the newspapers about positive aspects of the Nazi/Hitler rule and they believed.

They later learned (when the 3rd Reich collapsed and the war ended) what a mess the Nazis left behind with millions of deaths and eradicated families. Many people still of course knew what happened but we’re subject to repression or just went along with it. Propaganda still leaves an impression especially considering that many young people back then grew up wrapped in dense propaganda.

Now the analogy is that there were probably positive aspects of the Nazi Regime for some people. Since after the war there is a stereotype about people in discussions about the time saying “yeah, but not everything was bad!”. They might list things like that “Hitler” (the government) build Autobahns (which were invented earlier anyway) or hospitals or something else. Just like a government should care about its people. These people are correctly being punched in the face for saying this, as we all know that in the background the Nazis made half of Europe suffer from their ideology.

The punch in the face would be a downvote here, as Musk is not to be idolized as he is just a manchild with too much money and he does not care about humanity or humankind.