Revolts could be successful or not successful, with tech advancements in suppression (large scale surveillance, weaponry, various strike drones) chances of population to strike back become smaller.
Economy could totally be built around demand and wishes of super-rich, because human's greed and desires are infinite, new emperor may decide to build giant temple, and here you have multi-trillion economy how to make it running.
There are fewer than ten nuclear states, two of which have almost all of the nukes. All but four countries in the world are signatories to the Treaty on the Non-Proliferation of Nuclear Weapon. Only nation-states possess nuclear weapons, even the wealthiest corporations and individuals would be obliterated if they ever tried to obtain or build them.
The idea that no moat exists is folly.
The economy cannot be sustained on the demand of a small handful of wealthy people. At a certain point, you either get a depression or hyperinflation depending on how the powers that be react to the crisis. In either case, the wealthy will have no leverage to incentivize people to do their bidding.
If your argument is, they'll just get AI to do their bidding, you have to keep in mind that "there is no moat." Outside of the ideological sphere, there is nothing that essentially ties the wealthy to the data centers and resources required to run these machines.