He isn't saying "rich people are bad", even if some people want to misinterpret it that way. He is saying the ultra-rich shouldn't exist based on the constructs of a properly regulated free market economy.
I sort of understand that, but his language is just horrible. I'm perfectly fine talking about how the rich pay almost no taxes and such. I think it is a very easy sell to say that companies should be paying 20%+ taxes like the rest of us.
It isn't as much about policy as it is about narrative.
I realize that this is enhanced because they are purposely punching at Bloomberg, but this "all billionaires are bad" will come back and bite them. They will either have to walk it back or worse - alienate huge chunks of people.
These chants of "Wall Street Pete" because a guy happened to take some donations is a perfect example. Are they saying that nobody rich could possibly be on our side? That's a bad statement IMHO. I don't like Bloomberg much, but I don't hate him because he's rich. I hate him because he's out of touch.