This has been proposed in the past for tickets, but I'm not too sure how to approach it. What we're trying to avoid is every bit of junk email becoming a ticket and then having to dedicate time and effort into features to help manage all the extra junk. But I get that oftentimes important notifications come into the support inbox too.
Basically, I can guarantee if we turn every email into a ticket, the next request will be for how to block specific emails, subjects, etc. That adds a lot of bloat and creates more areas for email parsing to break.
The alternative approach I've seen with systems in the past is that unidentified contacts (emails from domains not registered in ITFlow against a client) go into a Web inbox of sorts. From there, they can have a ticket manually created or just be deleted/ignored.