I am not sure you can really do much for them beyond educating them on how the myth of evil authoritarian communism is an excuse for evil capitalist misdeeds, and how the neoliberal worldview is simply unscientific in many ways (it uses authoritarian and totalitarian as buzzwords with little meaning and much hypocrisy). If they are your friends, you could try to chip away at their misunderstandings, but you should really consider how willing they are to accept convincing.

Oh, you can also point out how liberalism tends to support fascism when they are able to control it (Ukraine and West Germany), so their moral high ground is unfounded (I know your friends are social-democrats, but they are still afflicted with some of the same propaganda): Such will likely give them quite a shock! :>