I think the problem here is defining what communism is supposed to be, or what constitutes these "political structures."

For Marx the "political structure" stems from the mode of production, what we usually call the base. In a very shortened form, it's the interacting between productive forces, means of production and the property regime (and all its consequences). As Capital tries to multiply itself, capitalism has shown a development of the complexity and productivity of the means of production, along with requiring workers that are able to deal with this complex production (specifically, this is dealt with by having multiple people act in unity towards a single product), in other words, developing the productive force. As capitalism develops, it accumulates property under a central command while simultaneously making it a collective tool. So, in capitalism's specific case, we're dealing with private property that is only used by a capacitated collective.

The developing self-consciousness and organization of this productive collective pressures the regime of private property, which will strike back violently to keep existing, in the specific form of blunting the collective organization at all costs, as well as pushing back against the superstructure reflexions of these changes (i.e. fascism). If the self-conscious productive collective is victorious, it has been through a period where: the means of production have been transformed; the productive forces have been transformed; the property regime has been transformed. Thus, we have a new mode of production, and a new "political structure."

This is the tendency of capitalism. But notice that this assumes a more or less constant development of technology, for example. What if climate catastrophes hit too hard too fast in the coming years? Parts of civilization could be severed from eachother, and develop in different ways, depending on what exactly gets destroyed. Would an electricity-starved modern nation still develop factories as we know them? Or would property get fragmented again? What knowledge and techniques would be lost or gained? That we can't predict.