Sorry, you are right. I have used this method for updating email addresses for sites that are using SAML login, and it works. For sites using password logins you need to do one more step.
After updating the user’s email address though the command line, go to the Admin / Users page for the user. In the Permissions section of that page, click the ‘Deactivate Account’ button. You will then see two new buttons, ‘Send Activation Email’, and ‘Activate Account.’ Click the ‘Send Activation Email’ button. This will send the ‘Welcome to Discourse!’ email to the new email address. The user can click the link in that email to reaccess their account.
If I find a more straightforward way of doing this, I’ll update my post.