I'm not sure about this - that seems too extreme of a statement. If there is any winner, it's going to be Windows. IMO, Linux and macOS will be within 5 percentage points of each other. From what I've seen at university, it's something like 60% Windows, ~20% macOS, ~20% Linux (usually Ubuntu). Much more Linux/Mac in the "hackier" courses, usually with a slight majority to Macs.
Where can reliable statistics be found on this? HN isn't exactly indicative of developers in general.
That's all I need to say about that.
As for the reasons.. Devs want a POSIX (macOS, Linux or BSD) system because many of the utilities used are written for that, and much of the infrastructure you will be working with in the future will also be POSIX. Of all the POSIXes, macOS is by far the most capable and stable laptop OS. Macbooks are still unrivaled, with only the Dell XPS range coming somewhat close.
They are also the only company with both a solid phone and computer product, meaning you get lots of ecosystem goodies (verify iCloud logins with a push notification on your iPhone, Wi-Fi passwords entered on your MacBook instantly work on your phone, 'instant hotspot', AirPods intelligent multi-pairing, etc)
And that may seem like I'm drinking the Apple kool-aid, but I'm not. The audio quality on the AirPods is terrible. In fact, Apple has never produced anything but mediocre audio gear. The $200 price bump on the MBP 2016 is unjustified. Removing the headphone jack on the iPhone is utterly insane, even if they did use USB-C (maybe in 10 years when all audio-out ports on everything everywhere also uses USB-C it would have made sense). macOS stripping out all GPL tools because they don't want to use GPLv3 stuff, etc. etc. etc.
Here's data:
https://stackoverflow.com/research/developer-survey-2016#tec...
~50% Windows, 26% OSX, 22% Linux, for the average "developer-who-fills-a-survey-on-stackoverflow".
And I doubt anybody will argue that the masses of developers who don't frequent StackOverflow are less likely to run Windows.
That's apparently the school of journalism...
Devs who write native apps for an OS (e.g. DirectX games for Windows) will of course use that OS.
In general, I see Linux native used as often as Mac native, and Linux VMs used on Windows all the time. POSIX has little to do with it.
That said, it depends on the kind of work; obviously, .NET developers almost exclusively use Windows, and I've noticed that sysadmins and system engineers are a little more likely to use Linux.
`GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin16) Copyright (C) 2007 Free Software Foundation, Inc.`
that's a 10yr old bash and there's barely any shell magic that you can do on Linux that won't work on macOS. And since by far most devs use macOS, most binaries support at least the macOS version of bash. All in all, no need to worry :p