The Mondragon Corporation

I'm sure you've all heard of it. If land and natural resources were collectivized, and all corporations turned into worker co-ops like the Mondragon Corporation, would the state still be a threat? It seems to me like provisions of this nature would reconcile the contradictions of capitalism. I kind of like the idea of nationalized healthcare/education/infrastructure. What would you all consider the downsides of the Mondragon Corporation? Do they not go far enough?