Nuke the data. It’s gone forever if you didn’t back it up elsewhere. This should be a meaningful risk mitigation that I can employ to avoid having a catastrophic financial disaster.

This isn’t a limit I’m setting at some percentage above expected costs, it’s: “I don’t want to take out a HELOC if something goes wrong”

Unfortunately, a lot of people keep their backups in the same cloud account as their primary data. Thinking that multiple copies and multiple availability zones are sufficient.

For these users, the article’s €54k bill would be replaced with their business data getting wiped out.

Read/write access should be frozen, data should be saved for 1 month so you have time to react to warning emails. If you didn't upgrade in that time, it should be deleted.