If you haven't read about Zuckerburg's underground bunker, it's like a fully stocked 5,000 sqft mansion. Lots of the billionaires are building underground doomsday mansions lately. Peter Thiel, Bill Gates, and Sam Altman are some of the names I know offhand, but there are reports that many silicon valley executives are doing the same thing.
It wouldn't be a wonderful way to spend the massive amount of time needed for the outside world to recover from nuclear fallout, and they're all building small shelters for individual families and their slaves, not the sort of larger community that would require. On the other hand they would be fantastic places to spend a few short years while an extremely transmissible deadly virus removes the bulk of the redundant humans cluttering up the world. The virus won't be able to live long outside of a human host, so if the transmission and mortality rates are high enough it really wouldn't take all that long for it to be safe to come out from hiding.
The bunkers all have extensive surveillance of the entire above ground region, so even if large scattered patches of humans survive they'll be able to be sure none of them are lurking around before hand.
Plus they've decided it's a great idea to combine AI, drones, and murder, so it's not like they'll be counting on a lot of henchmen with guns who could easily turn on them. AI is currently getting loads of training data right now on how to most accurately target the children in gaza who "look like they could use some food the most" and learning how keeping their center of mass in the happy food scope means they never see that same hungry child again.
Hooray for the future!