The best case scenario for an operational failure is the loss of a single AZ, but many of the scenarios you described are things that could impact an entire cloud vendor simultaneously. As others have pointed out (in discussing the Carrington event and the recent Facebook outage), it's not a matter of if it will happen, but a matter of when. And then it's just a question of duration and scope of the impact.

At this point around half of the world's leasable compute is concentrated in fewer than 100 facilities, the locations of which can easily be found with a google search. Using public satellite imagery you can identify network connection points as well as follow power transmission lines. In a wartime scenario, these are industrial targets with astounding strategic value, a tiny geographic footprint, and limited collateral damage in terms of human life. The Nagasaki and Hiroshima of the future could simply be kinetic attacks against a couple of datacenters. I'm alarmed that nobody is prepared for this and the industry zeitgeist seems to be to continue the consolidation of our economies into the cloud.