How big is said workplace? Can you respectfully ask for an exemption? Don’t say Windows will make you miserable (it makes everyone miserable, apart from a few Microsoft bootlickers), talk about loss of productivity, reduced security and increased risk, and – if you can – challenge the grounds on which the change is being made.

Often, they are incapable of providing proper justification for the change. May not help, but you’ll have the minor satisfaction of knowing it is bullshit.

Meh, does “the boss” pay you to use a shovel or to dig stuff up?

It’s obvious OP is going to be miserable and less productive on Windows, it’s not to their employer’s benefit for that to happen.