He's really wrong. Dem socialism is a misnomer. It's modeled after Denmark, Norway, etc, which are capitalist countries. True socialism is where the state owns all of the means of production and distribution and no democrat I know favors that, even progressives. He's wrong because there is a distinction, apparently he asked the wrong person, who didn't give a satisfactory answer (I'll agree that Bernie has never given a good answer, which frustrates me, but he is really the wrong guy to ask this question because he doesn't appear to have really thought about it that much, though he has proclaimed himself the leader of this movement ), nor is Ben interested in the answer, he's only interested in furthering a right wing agenda.
It's really the issue of semantics. if Shapiro wants to conflate socialism with democratic socialism, then I'm not a democratic socialist, nor do I now anyone that is who claims to be one given that I do not know anyone who wants a totalitarian society except, perhaps, communists. What Ben doesn't mention is that in modern times, the world "socialism" and really lost it's meaning.
So, if he wants to argue the flaw in socialism, fine, but it's a red herring given that, I, as a progressive democrat, do not support a complete removal of the profit motive from all industries, only health care, defense, social services, fire, and police and regulatory agencies.