Some doubt that Exchange Online will disable basic authentication for five email connection protocols in October 2020. The refrain is that it will be too hard for customers. Well, it might be hard to prepare to eliminate basic authentication, but if you don’t, your Office 365 tenant will be increasingly threatened by attacks that exploit known weaknesses.
Microsoft has released a preview of the cmdlet set to allow tenants to create and manage protocol authentication policies for Exchange Online. It’s a great chance to disable basic authentication and reduce the attack surface for password spraying.