You are betting that you can force developers to switch away
from Windows and MacOSX workstations.
Actually, I'm betting that "required to build product"
is a magic phrase that overrides corporate IT's desire
to brutally enforce a Microsoft-only environment.
Seems you are not part of one of these organisations.
That argument will not suffice.
I was, twice, and it did suffice. Try it:
"needed for revenue generation"
"required to meet customer needs"
...
Don't be taking away the ammo.
When the argument doesn't work, your organization
is obviously not fully committed to making a profit.
Politics are getting in the way. It's OK though,
since that just puts you at a market disadvantage.
Soon enough, the competiter will be hiring.