states exist to establish the supremacy of a class

Already we're dropping the pretense of eliminating class, which is the entire premise of communism. A system which establishes supremacy in any form could never hope to eliminate class.

Independence from socialism is a petty bourgeois notion, not proletarian.

And again you are uncritically equivocating socialism and the state. Socialism can and does exist independently of the state whenever workers collectively organize production and distribution anywhere and for any reason. Cooperatives are socialist, not petty bourgeois, because the workers themselves have collectivized the means of production. Small businesses that are privately owned are petty bourgeois.

These [socialism and the state] are one and the same in the context of a socialist state transitioning towards communism.

Always transitioning towards but never quite getting any closer and never will without the people themselves acting collectively to dismantle the state. The idea that the state will just "dissolve," or even more ridiculously disassemble itself, is absurd.

This slogan sounds nice, but ultimately just means that people should have a right to undermine socialism against the will of the people.

Again, people collectivizing the means of production on their own terms does not undermine socialism, it undermines the state. It's funny you suggest people acting on their own initiative undermines their own will, and not the state cracking down on them. I thought from our previous interactions that you were more reasonable than this.

a union in a socialist system is somehow "class collaborationist" for being official and supported by said socialist state requires a ton of heavy lifting on your part.

A union in any system that stops short of supplanting the boss and siezing the means of production is class collaborationist. Such a union in a capitalist republic is essentially just a bureaucratic arm of the company that serves as controlled opposition, and in a "socialist" republic is a bureaucratic arm of the state that exists to ensure the working class acts in the state's interest. You think the latter is acceptable because you believe the state truly represents the will of the people, but I believe that only the people themselves are truly representative of their will.