The purpose of software isn't to be correct or even predictable. It's to satisfy the needs of the user. The user in this case, isn't you. It's corporate clients who make decisions for tens of thousands of employees. They have various needs, however esoteric and strange. I promise you that all of the behavior you cited was implemented at the request of a client.

Ideally Microsoft should craft custom versions for specific clients, but that is its own nightmare. They tried that with Windows and it didn't go too well.