I disliked the anarchism erasure of portraying the Spanish civil war as a "communist party" cause (the authoritarian vanguardist type of communism that the movie focused on)
anarchists (well maybe except for insurrectionist anarchists) believe in communism as an outcome, but they most definitely do not agree with vanguardism as a means of achieving it. vanguardism is just a kind of elitist authoritarianism.
I would phrase it this way: (non-communist) anarchists believe in communal living as an outcome
Aware that this isn't historically accurate terminology but very few people will appreciate the nuances your definitions requires, as the modern meanings have diverged