Not sure if repost:
Nothing. If money didn’t matter there wouldn’t be anything for humans to do. As bad as that sounds.
Look at everything in front of you right now. Everything your human eye, ears, mouth, fingers and every part of your body can detect costs $. Even the dirt under your fingernail cost you money somehow some way.
Unless you also removed greed & generosity, the concept of value and worth (not talking about $), the idea of a need and a want, and everything else essentially holding a concept of value that when taken away would put the human race back to being an animal trying to survive and live a life… you can’t possibly conceptualize “if money didn’t matter”.
letting your mind run wild thinking about stuff like this is amazing to me.
But I love the concept hes talking about. Waking up to earn a living, is really not living life. 
I wrote a paper on this back in 5th grade that blew my english teachers mind. I wish I still had it to read it tomyself again. 
I see it as this: Everything in the world doesn’t cost any money to make, it only takes time.
there would be no need to have money, its just paper.
soon enough money will be worthless. It’s gonna be interesting when that does happen.
No matter what you want to do, even walk down the road, pick an apple and eat it, it costs “money”. The moment there are more people who want a “free” apples than apples on that tree, value is created. Ill give you my apple for your pet rock… bartering, is the basis of “money”.
its a chicken and egg concept.
Watch idiocracy, it plays out just like you said. The money ave tender was 100,000,000 haulin ass and getting paid dollars. Everyone except for one guy was essentially broke. its a funny, dumb, movie… but damnit its scary true.