So we all become totally materialistic hedonists...
Actually it *is* kind of hard to imagine that people would give up tribalism and warring upon each other... Holding hands, singing in the sunshine... Of course people don't neet religion to fight each other. Skin color, lifestyles, political systems... all can be (and have been) used as needed to justify murdering your neighbor.
No possessions is easy to imagine. Just read about how the Russians lived under communism. They had precious few possessions, but they didn't like it. Food appears as if by magic, greed is replaced by sharing, the whole world singing in harmony...
Yes, John, you are a dreamer. You dream that communism is the answer to all the problems of humanity, even after the horrors of the Russian experience, seventy some years of living as one, one desperate hungry poorly-dressed slave to the bureaucrats who administer a system like this. No, John, you are not the only one. There are other gullible fanatics who would similarly sell us all into slavery. You guys make Republicans look good by comparison.