my business contingency plan for "AWS shuts down and never comes back up" is to go bankrupt
Make sure you let your investors know.
You might as well say the entire NY + DC metro losses power and "never comes back up" What is the plan around that? The person replying is correct, most companies do not have a actionable plan for AWS never coming back up.
I worked at a medium-large company and was responsible for reviewing the infrastructure BCP plan. It stated that AWS going down was a risk, and if it happens we wait for it to come back up. (In a lot more words than that).
I guess the reason why people are not doing it is because it hasn't been demonstrated it's worth it, yet!
I've got to admit though, whenever I hear about having a backup plan I think having apples to apples copy elsewhere which is probably not wise/viable anyway. Perhaps having just enough to reach out to the service users/customers suffice.
Also I must add I am heavily influenced by a comment by Adrian Cockroft on why going multi cloud isn't worth it. He worked for AWS (at the time at least) so I should have probably reached to the salt dispenser.