The biggest issue for a lot of people is going to be Microsoft forcing all Office 365 users to use Edge all the time. Our sysadmin recently forced me to uninstall Firefox and Chrome from all workstations unless they had an approved use for it. Everything must be through Edge.

Why? "Security" of course. It's always "security". Curious

Edit: the point is Microsoft could have worked to provide enterprise customers with ways to manage third party browsers going forward. They could have worked with Google and Mozilla to make that happen. They didn't. Not really.

It's that Microsoft continues to make decisions that create rationale for only using them, because that's their business. "Security" gives them an extremely convenient cover for anticompetitive behavior. Anyone that thinks their C-Suite hasn't pulled the defender/365 team into a meeting or two to discuss business strategy has far too much faith in a corporation that deserves very little.