Usually it means someone that actually reads history and will specifically debunk common anticommunist myths about it, i.e. historical revisionism.

The term "authoritarian" is also used selectively by anticommunists and this pervades capitalist societies, who continue to teach cold war nonsense. It is implicitly reserved for actions of the state, for example, but this is a false distinction made solely because after any kind of a left takeover, the state is the most powerful tool the people have. Universal government healthcare is authoritarian by this selective definition. On the other hand, the assertion of massive control over people's lives is not described as authoritarian when it comes from the private sector. Workers spend 8-16 hours per day working in petty dictatorships, working around the personalities and whims of business owners and managers, just to ensure some kind of steady income lest they lose basic human security. They are forced to migrate by poverty forced by capitalism, this system creates marginalised groups and then (sometimes slowly) treats them genocidally. Much of it was built on colonialism and neocolonialism, with the richness of the West built on uneven exchange with everyone else, a system set up at gunpoint. None of this is described as authoritarian.

Please read more widely.