Since there is still no way to force the user to set the 2FA, we have created a Powershell script that checks the status periodically and sends out emails. We have decided to let only the administrators know about the status, hence we send the email to them instead of the user.
Could you imagine to script that for your own and use the REST API to get the status and let Powershell or some other languages send emails?
I have already voted for your idea and therefore support your request fully. For all others, a reminder might help in case they have no idea at all. Also good to know that you still “fight” for you idea …