There really isn't a great way to clean things up, and using GAM to edit a user's personal contacts is reasonably invasive privacy-wise. (For example, maybe I have a contact called "Boss", with some additional details about my boss like his family's birthdays or his home address. I might be kind of annoyed if that contact got deleted, even if he did change his email address.)
See below for a a thing I wrote up a year or so ago about people changing their lived name, and how this brokenness in Google is problematic. It also illustrates the overall problem pretty well.
The following setting in Gmail is on-by-default (it’s in Settings > General):
That feature is really pretty handy, for lots of reasons, and turning it off would have some pretty negative impacts to the usability of Workspace.
BUT there’s a serious bug in that feature. The auto-saved contacts in “Other Contacts” override the local Google Workspace directory.
That means that for people who change their lived name, anyone who ever sent an email to them before they changed their lived name will continue to have Gmail autocomplete the dead name, even if the person has properly updated their lived name in the Workspace directory.
This is a very subtle wrinkle of this feature, and I’m sure an unintended consequence, but it is leading to a fair bit of hurt, and therefore angry tickets, for us.
Due to the nature of the feature, it’s also incredibly unclear to either the email sender or recipient as to why it’s happening, which amplifies the hurt. (It took me half an hour just to explain it to my team, much less anyone else!)
A good potential fix would be to make the person metadata (name, department, address, etc.) for Other Contacts from within the same Workspace instance stay in sync with the directory rather than being a point-in-time capture.
Or maybe to make it so that Other Contacts aren't added at all for addresses within the same Workspace instance.
Or maybe change the current hierarchy of lookups for address autocompletes from the current ordering:
1) My Contacts (the ones I’ve explicitly saved/edited)
2) Other Contacts (the ones auto saved by the feature above)
3) Google Workspace directory
to:
1) My Contacts (the ones I’ve explicitly saved/edited)
2) Google Workspace directory
3) Other Contacts (the ones auto saved by the feature above)