It transitions back to a more feudalist state. The series finale to "you will own nothing and be happy."

That is, if they're successful.

Not much. Early economies relied on mutual trade. I give you X and in return you give me Y. Soon we realized that you cannot always give Y in return immediately, so we invented accounting to keep track of your promise to give me Y at some point in the future. As time went by eventually we stopped caring about getting Y back in return and started taking an interest in collecting the promises themselves (i.e. profit).

Why would someone want to collect promises? That seems rather silly, right? What having a lot of promises gives you is social standing. People treat you differently — better — when they give you their promises. If traditional labor goes away, the economy simply becomes you promising to hold those who have things in the highest regard; to be there as their friend when they call for you to. That is the same modern economy we already have but with less steps.