Data centers are usually built to withstand local natural risks e.g. weather. All bets, SLAs, and insurance are usually off when it comes to acts of war.

There's also just an upper limit to the kind of risk you can reasonably defend against.

An out-of-control wildfire levels the entire city? The Big One hits the Bay Area? The entire city is flooded for a few months because the levees break during a Cat5 hurricane? Yeah, your DC will be completely ruined. And even if it isn't, you're probably not getting any outside power, generator fuel, or repair technicians for a while.

No matter how much money you pump into hardening your own super-bunker DC, there will always be disasters you aren't prepared for. At a certain point it just makes more financial sense to abandon the idea of invulnerability and build a redundant site a few states over. Accept that you will occasionally lose one, and only protect against incidents where mitigation is cheaper than occasionally rebuilding.