No one is ever going to be "saved" by a doomsday prepper bunker because it's entirely too expensive and unrealistic to maintain enough air filtration, water, food, medicine, and power generation/energy storage for even a single person to live sealed away for the rest of what would be their ordinary "natural" life. Preppers really therefore should be thinking self-sufficient farming/homesteading and essential medicines and supplies for common condition and acute injuries... but billionaires want TV dinner, safe room palaces so their selfish choices won't ever affect them in their minds.