What is currency but a proxy for time spent/labor? Today, different peoples labor is exchanged for different values of currency.

If we reach the era where labor isn't necessary for the majority of daily life, what value does labor/time offer anymore? Why would a seemingly very low value commodity (labor/time) be used as a value exchange medium?

There may be a new thing that is developed as a pseudo-currency, based on some other intangible-value-made-tangible, but it wouldn't be a stand in for labor/time in this entire very made up, very simplistic scenario.

Something else would carry value, assuming the entire society is into personal possessions at that point. This may evolve into a communal situation for all we know. Post-need generations would have no need to accumulate. There surely may be some experience, travel, etc that may drive some, but even that may be trivial.

There is zero reason to apply your personal beliefs about the past to future societies that don't have the same restrictions or priorities.