most people are not willing to learn an entire new operating system for no reason, though. this might happen in tech-based companies, sure, but banks? accounting firms? ive never seen them offer macbooks.
this is also ignoring all of the critical software that is windows-only (e.g. quickbooks, solidworks, bespoke programs in banks and government).
point is: microsoft is not in "significant danger" today.
My daughter works at a bank in Canada and she was issued a Macbook.
Most people dont even use the operating system. They look for the apps menu, then click what they want to run. Most people can switch between OSes easier than you think because there really isn't that much difference in how they work on the surface.
An increasing number of people are coming into the workplace never having used a Windows machine, or only occasionally having done so when it was absolutely necessary.