@woody Literally no idea what any of this means because its written for tech people. So as a non-tech person I have no idea what I need to change or how I will be effected.
Google and Microsoft have been trying, for the last fifteen years or so, to turn email from an open-standards based commons, to a walled garden in which it's impossible to send or receive email unless you're a customer of one or the other of them. They've been making it more and more difficult for anyone who's not a customer of either Google or Microsoft to send mail to, or receive mail from, anyone who's not. That mostly consists of silently discarding emails which should cross out of the walled garden, and then vaguely blaming everyone else. Also a lot of hand-waving about spam and security. This particular change is about prohibiting their own customers from using non-Google apps to access Google mail.