I wonder, will the rich start hiring elaborate casts of servants including butlers, footmen, lady's maids, and so on, since they'll be the only ones with the income?
They already do. In fact, we are all working in service of their power trips.
They already do and always have. They never stopped hiring butlers (who are pretty well paid BTW), chefs, chauffeurs, maids, gardeners, nannies.....
The terminology may have changed a bit, but they still employ people to do stuff for them
One big difference is while professional class affluent people will hire cleaners or gardeners or nannies for a certain number or hours they cannot (at least in rich countries) hire them as full time live in employees.
There are some things that are increasing. For example employing full time tutors to teach their kids - as rich people used to often do (say a 100 years ago). So they get one to one attention while other people kids are in classes with many kids, and the poor have their kids in classes with a large number of kids. Interesting the government here in the UK is increasingly hostile to ordinary people educating their kids outside school which is the nearest we can get to what the rich do (again, hiring tutors by the hour, and self-supply within the household).
They also hire people to manage their wealth. I do not know enough about the history to be sure, but this seems to be also to be a return to historical norms after an egalitarian anomaly. A lot of wealth is looked after by full time employees of "family offices" - and the impression I get from people in investment management and high end property is that this has increased a lot in the last few decades. Incidentally, one of the questions around Epstein is why so many rich people let him take over some of the work that you would expect their family offices to handle.
Who do you think is building the machines for the rich? All of these tech companies are nothing without the employees that build the tech.
This is what the service economy in the imperial core already is.
As far as I can tell, the rich have never stopped employing elaborate casts of servants; these servants just go by different titles now: private chef, personal assistant, nanny, fashion consultant, etc.