Why would they want to encourage people to buy x86 machines from vendors other than them?
Linux has been rare mostly for compliance and regulatory issues - corporate IT thinks it’s too easy for a determined Linux geek to take over the machine and bypass all safeguards.
And that's because it is... when Grub boots, press e, add init=/bin/sh (or rdinit), and boom you have a root shell. In case the admins did think far enough to deal with implementing Grub password protection or secure boot of some kind, wait a couple months, and there will be some sort of local privilege escalation exploits (there's about one a year).
In addition to that, Linux doesn't exactly play nice with corporate snake-oil solutions - these are more hassle than they're worth it as they constantly break.
So they wouldn’t buy any macOS licenses unless they are <$50 either? Which makes it totally not worth it and would result in a significant decline in revenue for Apple
Outside of the tech departments staff usually get generic corporate hardware for light desktop/browser workloads.
Of course, most companies aren't going to spend on a Mac laptop; a $500 Windows laptop (or whatever) is usually good enough for many roles.