Considering the state of current democracies, I don't think I could trust my peers to make sound financial decisions at an organizational level collectively. It's different from a democracy in government because I can, without much friction, leave a company at any time if I feel that the company is not doing well, not so with a nation-state.

I personally have started and run a coop, but that worked because we were all friends who wanted to collectively pool our resources to get new clients as a software agency, if it were a larger cooperative, I would agree with the sibling commenter that they generally do not work as well as top down corporations.