This has nothing to do with blueprints for dictatorships and totalitarian regimes. It has everything to do with seriously confronting capitalism. The case for communism would have been won decades ago were it not for the Stalinist monstrosity that dominated a third of the planet for half a century or more. This was not communism, but state capitalism of the most authoritarian and centralised kind. It was the opposite of the Marxist criteria for communism.
Communist society is about the abolition of the state as an instrument of repression and class rule.
It is about local committees and soviets linked in a system of economic co-operation of free exchange. It is about the abolition of wage labour, and the accumulation of the wealth created by that wage labour as capital, which becomes a power against the workers. It is about production for need. Just as Labour never has been socialist but has been a party for the management of the national capital, so too is the Socialist Alliance. It calls for nationalisation of the railways and other industries.