Under age users - could they store their own data until of age?

Question

Basically, I'm revisiting this question: Under age users - could they just be suspended until of age? Instead of immediately deleting an underage user's data, consider the following protocol:

Underage user protocol:

1. Stack Exchange creates an encrypted ZIP file of that user's data,
2. Stack Exchange securely stores the encryption key,
3. Stack Exchange sends the encrypted ZIP file to the underage user [who cannot decrypt it],
4. Stack Exchange deletes the user and the encrypted ZIP file [keeping the encryption key, containing no PII].

In this way, the underage user stores their own PII---if they delete it, it's permanently gone. And it's not decipherable in the unlikely event that it's sent to the wrong user. Stack Exchange does not store the PII of an underage user.

Protocol when they reach age x (where x is their locally required age):

1. The underage user sends the encrypted ZIP file to Stack Exchange [if they choose to do so].
2. Stack Exchange decrypts and restores the user's data onto Stack Exchange.

Would this work?

Answer 1

We are not interested in going down that route, because it is very rare that we get underage users with large amounts of content where it is painful to have to delete their account. In those rare circumstances where it does occur, we usually give them their old profile URL and tell them to come back to us when they are of age and we will restore all of their past content.

We can reassociate all their past posts and comments to a new profile down the road, and have done that for some users in the past. All it requires is knowing the previous user Id number. That is why we give them their old profile URL to hold onto (because of the way underage deletion works, it is not possible for us to look it up again once the deletion is performed).

However, all this work does not benefit most users. The vast majority of underage users that get deleted ask low-quality questions and would not benefit in any way from having their past content reassociated to them. They'd be better off starting with a clean slate. This process is reserved for high-reputation users that we are forced to delete.