No corporations, no profit based businesses, no state. Only non-profit organizations. Would this be communism?
If so, could this possibly be self-sustainable? How can such decentralized society structure possibly self sustain without the threat of centralization?
You mean non-profits but without a specific prohibition to create corporations? Well, I believe that could work. A corporation can’t compete with a non-profit in the average case, even in a free market economy, so you really wouldn’t need to do anything for it to be stable. I don’t know if that would count as communism tho… A non-profit doesn’t have profit as a goal, but what does it have?