It also sounds like an implied admission, on the part of evernote, of not having working backups ? I would think that they would have found some way any way to get your data back to you given what just happened.
For that matter, isn't the (or one) reason for having a backup so that errant deletes don't obliterate everything?
In the long term everything suffers from "data decay". It's just too hard to keep old files around forever.
E.g. there were comments I made on Usenet many years ago. Google has previously attempted to preserve those, but they seem to be fading away into the ether. That's okay by me.
Fortunately there is no strict time limit on completing this process so a design that looks like "and after X months it will have aged out of our backups" appears to be considered reasonable. You are still responsible for making sure your backups are safely destroyed.
They also took like two weeks to respond to my problem ticket. I'd submitted it on New Year's Eve, so I anticipated having to wait a day or two, but that was pretty ridiculous.
I think a middle ground would be a two step deletion, no?
Step1 : Delete from everyone's machine but keep a backup for X days to allow people to file complaints etc.
Step2 : Delete Backup