Here we observe the not-so-subtle attempt to shift the debate from "social democracy" to "collectivism", as if the two terms are synonyms.Exactly what is the difference between "social democracy" and "socialism?"
In particular, how is there a system of checks and balances to keep the voters from appropriating everything, thus handing all of the power to the central government and thus initiating totalitarianism?
We also see a denial that mixed economies with strong social safety nets can ever work on, say, the scale of a nation. Despite plenty of evidence available, in the real world, that they can.
It can be argued that all existing economies are mixed economies.