Sure, there are plenty of alternatives, many are superior, but because of inertia and policies it's difficult to eradicate Microsoft variants. That's why many of us have to put up with broken products like Teams on a daily basis even though everybody (i.e. users, middle management, top management) know they're broken and half-useful when compared to competition.

Changing Operating systems is not a small feat. Also there are MANY enterprise applications that depend on windows, windows server, or Microsoft SQL server. It is not an easy task to migrate away from those. That is why companies pay Microsoft $$$$$$ in licensing.

to be fair microsoft are head and shoulders above the rest when it comes to openly treating their paying customers like shit.

Oracle and Adobe are highly competitive in this space as well.

Anything that involves lazy executives that prefer bundling and shaking hands with one account rep that gives out free dinners and booze.