The golden goose is now Azure. Windows is (or will be soon) a free complementary OS to make more people use Azure services.
This I find baffling. Outlook and One Note are some of the worst applications known to man. Clunky interfaces and confusing messes to navigate.
I was recently trying to integrate EasyAuth OIDC with a custom IdP and it was a terrible experience. No logs indicating why it wasn’t working. I had to dig down into the configuration xml schema to discover EasyAuth didn’t even support client_secret_basic auth method so we couldn’t use it in the end. Every product is like this. Great if you do everything MS wants you to do exactly, but if you have any requirements not blessed by Microsoft you’re SOL.