We won't keep copies of content anywhere, so users will be free to permanently delete their email, docs, etc. But when content ...

We won't keep copies of content anywhere, so users will be free to permanently delete their email, docs, etc. But when content reaches the age you choose, we'll delete it from where it lives. For example, email messages and calendar items will be deleted from users' mailboxes and docs will be deleted from their SharePoint or OneDrive libraries.
Good news is you'll have a short time to recover the stuff that's been deleted before it's gone for good.