When accessing the preferences tab of a user profile from another user as a moderator, I see the following:
Unlike the other places where the user mail address is shown, it is shown by default without moderator interaction here. Usually there is an explicit second click required to show PII.
Viewing this tab also doesn't lead to an entry in the user history about a moderator accessing the email address, unlike all other actions on the user profile that would expose PII.
There's really no reason to show the mail address here at all for regular moderators, so it might be the easiest way to just not show it at all. Otherwise it should have the same click-through like everywhere else.