Um….. I’ve eaten in many three-toque Guide Michelin restaurants across France, the UK, and the USA. In the case of the latter they’re consistently disappointing, being merely there to enable moderately wealthy people to display their wealth, just like opera houses and concert halls. So I can see where you get your preconceptions from. But in Europe people truly like food; we go to expensive restaurants not because we’re poseurs or super-rich but because actually a great chef will make food that you simply can’t prepare at home, even if you had the slightest idea how to do so. The experience of one course following another in perfect harmony, the flavors and textures all complementing each other, is something impossible to imagine if you’ve only ever eaten in the USA. So these restaurants won’t disappear because there are enough middle-class folk who love food enough to save up & go once or twice a year.
As for today’s super-rich deserving their wealth, you may want to do a bit of research: there’s not a tech billionaire out there who wasn’t already hugely privileged before they even began.