According to a recent CRA report and some verbiage on their website, they're going to be requiring everyone with a CRA My Business Account to register with an email address. I know, in my experience, that I still have a couple of clients that don't even have an email address, a smart phone, or heck even a computer. 

They've also made it a requirement that all CRA My Accounts must have an email address and it started in February of this year. This is in preparation for 2023.

In 2023, if you file your tax returns using EFile, Net File, or any digital format, you will receive your notice of assessment digitally instead of through the mail. You can get exactly the same thing online right now, which means that your accountant can get them as well if they have access to your account through Represent a Client. In my opinion, this is a little bit more convenient. Obviously you're not getting mail, opening it, keeping it in a drawer. You can access it online anytime you want and/or save it to your online storage.

I’m not sure how those people who don't have email addresses, computers, or cell phones (yes, they do still exist) are going to handle it. It's going to force their hand a little bit, but I think it's for the best.

So you're going to need an email address to access your CRA My Account 2022, and then in 2023 you're going to start getting your notice of assessments of CRA digitally. Hello new world!