Add to this the different varieties of their apps. The whole MS thing is a mess imo also because it cannot decide if it is for enterprise or for personal use. Some colleagues had to reinstall outlook, and after that things did not work properly. What actually happened was that they had googled and downloaded "outlook" from microsoft's website, instead of installing the m365 suite version. Which is basically a different application or version or whatever, but sharing the same name and app icon.