" Which races do they believe in exterminating again? I forgot."
I'd put it in the 10s of millions of people is the amount of people that they want exterminated.
It would include all bourgeois, petite bourgeois (ie small business owners), as well as anyone else that would oppose them in an attempted overthrowing of the capitalist system as their attempted "dictatorship of the proletariat", as well as anyone who supported the current "imperialist regime" of our capitalist system. IE, probably most police officers, soldiers, and politicians.
So yes, in terms of total number of people that they want to kill, I'd say it is about equivalent in badness to literal Nazis.
"Liberals say that liberals get the bullet too?"
Ah, see, here is the confusion. You don't spend much time listening to leftists. (Otherwise you'd get the "liberal" reference)
In communist and anarchist circles, a "liberal" is not in reference to an american leftist. They are talking about classical "liberals" as in someone who support civil rights and civil liberties, and the capitalist system. The "liberals" are the enemy.
Bernie Sanders and Corbyn are not socialists to these people. Neither is Norway, or Sweden or European social democracies. You are only a socialist if you believe in the violent confiscation of the means of production, and the overthrowing of the imperial capitalist system.
Modern day Venezuela is the kind country that they support, but they don't even think that Venezuela went far enough, and don't even think it is correct to call Venezuela socialist.
Go read reddit /r/socialism and /r/Anarchism and read the comments to understand what leftists believe.
I read them every day. It is enlightening.