I am under the impression that "Erase deleted messages…" applied ONLY to messages in the Trash mailbox? At least that is how it appears to work in Mac OS 11 and 12.
Sorry to be unclear. I was referring specifically to messages that Jon's wife had already deleted, since he said
She deletes as many emails as she can...
I just wanted to clarify that server space continues to be occupied by those deleted messages until they're erased from the trash, which may be some time later.
