Bloomberg did score points at the debate when he was making the case for capitalism and challenging Sanders' socialist agenda

Legal Insurrection:

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In the meantime, the few solid blows Michael Bloomberg landed against frontrunner Bernie Sanders during the Democratic debate were practically tailor-made for the Trump campaign to use in future ads against Sanders.

Here are three of them:

1) After Sanders bemoaned the so-called “grotesque level of income and wealth inequality,” he claims exists in America and said in so many words that billionaires like Bloomberg should be more on board with sharing more of their wealth, Bloomberg hit back hard.

Bloomberg told the moderators he would “absolutely not” support what Sanders was proposing. “I can’t think of a way that would make it easier for Donald Trump to get reelected than listening to this conversation. This is ridiculous. We’re not going to throw out capitalism. We tried that. Other countries tried that. It was called communism, and it just didn’t work.” As Bloomberg said that, both Sanders and Sen. Warren audibly groaned and raised their hands to respond.
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Sanders later asserted that it was a “cheap shot” for Bloomberg to use the word “communism” to refer to socialism.

2) Moderator Lester Holt asked Sanders about a recent NBC poll where two-thirds of voters said they were “uncomfortable with socialist candidate for president.” Sanders defended his belief in socialism in the full minute and a half. He spouting off his usual pablum about how the system’s structure benefits the wealthy and not the working man
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Bloomberg blasted back by pointing out that Sanders had done exceptionally well for himself in the very American capitalistic society he denounces:

HOLT: The question was about socialism.

BLOOMBERG: What a wonderful country we have. The best known socialist in the country happens to be a millionaire with three houses. What did I miss here?

SANDERS: Well, you’ll miss that I work in Washington, house one.

BLOOMBERG: That’s the first problem.

SANDERS: Live in Burlington, house two.

BLOOMBERG: That’s good.

SANDERS: And like thousands of other Vermonters, I do have a summer camp. Forgive me for that. Where is your home? Which tax haven do you have your home?

BLOOMBERG: New York City, thank you very much, and I pay all my taxes. And I’m happy to do it because I get something for it.

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3) When asked if he felt Sanders could beat President Trump, Bloomberg hit him on his Medicare for All plan:

BLOOMBERG: I don’t think there’s any chance of the senator beating President Trump. You don’t start out by saying I’ve got 160 million people I’m going to take away the insurance plan that they love. That’s just not a way that you go and start building the coalition that the Sanders camp thinks that they can do. I don’t think there’s any chance whatsoever. And if he goes and is the candidate, we will have Donald Trump for another four years. And we can’t stand that.
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The reason Bloomberg looked bad was not because of these things, but because of the withering attacks on some of his previous statements that were impolitic. In making the case for capitalism and current medical insurance Bloomberg exposed the rot at the base of the other candidates' attacks on a system that is creating prosperity for millions.