Teams Telephony/Calling - Global Telephone Book

Is there a way to create a global telephone book for Teams Telephony? A search returns results for accounts with O365 licenses, but not shared mailboxes, contacts, etc.

Each individual having to enter a contact for critical numbers seems like a waste of time, when a search function is available and could search a global telephone book.

Is this feature being considered? Going to Teams for telephony is actually a step backwards from a PBX (which has a telephone book).