That would make sense giving her the benefit of the doubt, thanks. The transition to metaphor was pretty blurry in the article title.

As I pointed out elsewhere, they can just forward the email to the intended address as an unwelcome MTA, so I disagree with your statement that they can't get people's email back. I agree on the time and reputation points though. However, I don't think any rollback has ever gotten those back, so 'rollback impossible' because it can't do what any rollback has ever done seems disingenuous.

I don't understand why you can't undo the damages ?

Just restore from your last iCloud or Device backup.

What if the "new" addresses have already been backed up over the good backup?

As silly as it sounds, this almost sounds like a job for Git. In that case, you could simply revert a single commit, and have the user resolve the conflicts. For that to work well though, you'd need to keep separate "repositories" for phone/Google/Facebook/whatever addresses and merge them locally, which could get very ugly for end users.