I'm pi**ed with Win 10.

[Tay]

There is an awful lot of software out there that just isn't written for Macs or other 'nix machines.
At work I support a radiooncology management system that is written for Windoze and most of the machines it connects to are Win, with the occasional 'nix system thrown in when we need a PC that simply cannot ever crash (Very old, command line only, super stable versions of Linux).
Apple simply don't get a look in (even though our software development site is just up the road from Cupertino)  because they don't allow developers access to the kernel, thus preventing the kind of interactions we need.
For home use or for graphics/media OSX is good, but in an industrial/business environment, they are nowhere.

There is very little windows software that I can't run on my mac, either as a VM or Crossover. My Audi diag software simply wont run on Windows anymore so I have an XP VM on my Mac Book.  Whats really annoying is that a 2-3 year old Dell Laptop isnt fully supported on Windows 10, pretty crazy.

Never had an issue yet, one of the big issues with the likes of the NHS and those many types of specialised software is that as newer Windows refuses to support older apps you are stuck into paying vast sums to upgrade to the latest flavour for support purposes  (assuming the company still exists) or you run unsupported OS's, and this is what a lot still do.

Mac's arnt for everybody though, likewise Unix/Linux, but for many 'it just works'.. I think that phrase is becoming less so these days, but the quality of the kit is second to none and the eco system will support it for many years to come.

Apple are the 4th biggest PC manufacturer in the world, I have also seen them in business environments,huge installs in Education too, and you know that with Apple kit you often are a generation ahead of windows PC's as Apple work closely with Intel, but you do need a compelling reason to use them, although the TCO stacks up well against Windows devices.

As for Apple not being in business environments, I've not visited many windows only graphic design firms.  As I said you need a decent business case for Mac's due to the cost.  In my view though, its well worth it. Until I sold (yes, sold) my Mac Pro 2009 last year, it was my main go to machine for 6-7 years.   I went through many windows laptops and PC's in that time :)