What's a non-oppressive state? One that currently exists, preferably.

It's nauseating hearing people talk about the nature of "real communism", like undergrads in Guevara t-shirts who have nothing but religious language to describe it because they have never studied the subject beyond cultural osmosis. Quoting Engels:

The 'people's state' has been thrown in our faces by the anarchists to the point of disgust, although already Marx's book against Proudhon and later the Communist Manifesto say plainly that with the introduction of the socialist order of society the state dissolves of itself [sich auflost] and disappears. As the state is only a transitional institution which is used in the struggle, in the revolution, to hold down one's adversaries by force, it is sheer nonsense to talk of a 'free people's state'; so long as the proletariat still needs the state, it does not need it in the interests of freedom but in order to hold down its adversaries, and as soon as it becomes possible to speak of freedom the state as such ceases to exist. We would therefore propose replacing the state everywhere by Gemeinwesen, a good old German word which can very well take the place of the French word commune.

There is no pretense by the PRC that they have reached the final stage of socialism, referred to there by Engels as Gemeinwesen and usually called today simply "communism". They have never held except that they are in a transitional state, as all socialist states are and must be so long as [neo]liberal capitalism is part of the world order. A little isolated commune can do little else but stay afloat itself. A massive commune can do little else but be steamrolled by its capitalist encirclers.