We run a Mac and Linux setup here - me being the admin, this is tolerable. Mac's still-essentially-Unix underlying OS makes this reasonably consistent - I can SSH between either platform fairly easily, for example. We offer new starters the option, and are about 50/50, though I've had a few surprises - one user had only previously used Windows, and from experience these sort of users switch to Mac more easily than Ubuntu, but he gave his MBP back after a day and switched to Ubuntu instead, which he's stuck with. I could not be more proud :D

It's very nice to give end users the option - when I joined, I asked for Linux and was given a brand-new Dell XPS with Ubuntu pre-installed, root access, and told, customise it to suit you. I keep that spirit with my users.

Throwing Windows into such a setup is a nightmare though - two users actually installed their company laptops with their own personal Windows 10 licenses without my knowledge or approval - I still hold a grudge because I had to actually read the MS EULA to make sure they weren't about to cause trouble! It means I can't manage them (I have no real tools to do so on Ubuntu), so they're on their own for that. Fortunately management has my back, declaring the company to be a *nix shop.

Our actual product is all containerised so it should run anywhere.