> If one power failure can take down more than 5 banks, what you are describing is a valuable target. It's ironic that the cloud services that promised to harden systems have delivered another layer of vulnerability.

Fair, but if all of those 5 banks bought their own servers and put them into a datacenter that happens to be same one because it's the fancy one that meets all the bank regulations and required certs, that datacenter going down would still make 5 banks go down.

You would got some resiliency by fact only datacenter related issues (power, internet access) would affect it and not say "cloud company throwing AI at their code that proceeds to explode" (which already happened), but still, if you want to fix that, cloud or not, you have to have multiple locations/regions and that's both costly and difficult.