This is one of the most silly aspects of this scheme that blackpillers and schizos use on the internet. Okay so they are locked up on an island. "safe" right?
These people are going to be eating cold beans from a tin for years? When they are supposedly elite nepo baby's who have never worked a day in their lives? They are used to the best roast beef, the best oyster's and the best caviar. You mean to say they will tolerate a massive decline to 3rd world living standards. Just to "survive" a civilisation level collapse? Who is going to power the bunkers? How are these elites going to fix a broken generator? They would die a month after everyone else tops.
Who the fuck is going to be collecting their food? Slaves? Too risky one of them might kill them in their sleep, no fucking rules in a SHTF. Robots and AI? Still need fixing when one breaks down.