The advantage of democracy is that the propaganda game gets played every few years and current elites can lose. Under a system of freedom of speech, there is very little stopping a decently (but not massively) funded rag-tag group of competent individuals from running a more efficient propaganda campaign than the powers-that-be (think of Dominic Cummings' Leave campaign in the UK for the perfect example).

This is the best system we have found to establish the impermanence of the elite class. Because this is the real beauty of what we in the west call democracy: not the absence of an elite class, for there is no such system, but it's impermanence.

And while that is all well and good within a country, the argument is that it would be unwise to allow a foreign hostile power a seat at our propaganda game. Especially one which does not reciprocate this permission.