The purpose of money is to trick farmers into producing food for everyone else so nobody starves. Any system where that happens is working acceptably. The inflationary fiat system is better at it than the gold standard - you'll recall there was a great depression and people were unhappy about it.
The luxury space communism idea where everyone just gets infinite money unfortunately has no evidence it'd work, because the farmers wouldn't believe you. The earlier systems, historical communism and feudalism, worked without money because you'd just have the farmers killed if they complained, but obviously that was problematic.
"The luxury space communism idea" usually has an expressed or implied removal of scarcity as an issue. If there's unlimited supply of goods and services, then there is no need for money.
On the other hand, most sci-fi of this nature also has semi-military structures and the military is the ultimate form of communism.
1. your idea probably isn't post-scarcity, you've just forgotten that the goods/services you want to automate have inputs themselves that still cost something.
2. if robots are smart enough to produce everything for us, they're probably human-level intelligent, could be customers instead of producers themselves, and so you've actually rediscovered slavery.
The luxury space communism idea where everyone just gets infinite money unfortunately has no evidence it'd work, because the farmers wouldn't believe you. The earlier systems, historical communism and feudalism, worked without money because you'd just have the farmers killed if they complained, but obviously that was problematic.