I did find an online posting that suggested that the most recent Mail v16 can be made to work with Rogers/Yahoo because, like Outlook 365, it does "modern" authentification without using generated passwords (I'm reporting the conversation as best as I remember, I know very little about this subject). Does anyone know if this it true?
In the meantime I will do as others have suggested, which is to set up a Gmail account that gets all my Rogers/Yahoo emails and create a MacMail account to connect to that Gmail account.
I find it a little nuts that Rogers/Yahoo simply stops supporting email servers such as MacMail.