That's misleading and deliberately misses the commenter's point. The DSA explicitly rejects authoritarian models of socialism (USSR, DPRK, etc).

The red-scare-fueled conflation of democratic socialism with basically Stalinism is largely what drives the general disfavorability of "socialism" in these sorts of opinion polls.

It's not like people were asked, "Do you favor ordinary people having a real voice in their workplaces, neighborhoods, and society? Do you favor a higher minimum wage, universal health care (Medicare for All), strengthening labor unions, and increasing the power of working people while weakening the power of corporations?"

People broadly support those things, but would very likely hesitate to call that democratic socialism (which, spoiler: those are the DSA's core tenets).

But what are his socialist policies?

His platform isn't socialist, nobody but him knows what his actual convictions are. I think he's a pragmatist, and knows that saying "I'm going to abolish private property day 1 and liberate the working class from their capitalist masters" is more likely to get him assassinated than spark a proletarian revolution. I personally believe him when he says he's a Democratic Socialist, it's just that he favors reform and is focusing on what's doable in the short term. The DSA has committed to what they call the "party surrogate" strategy, of which Zohran's campaign was a part. It means they intend to run insurgent campaigns on the Democratic ballot line while acting independently. With enough primary wins they can operate as a socialist faction within the Democratic party, which could theoretically split from the party and go truly independent after reaching a critical mass of support.

Here is a link that explains it more in-depth.