You can set up build servers for your app on Microsoft Azure, or AWS' Windows Server instances. Microsoft produces articles on how to do Windows development on a Mac (Bootcamp, Parallels, etc.) [1]. Microsoft has shown commitment to bringing it's core offerings to other platforms. Apple has in no way done that. You literally, absolutely need an Apple computer for every step of the development process for iOS. Your comparison is not valid.
Is it really developer hostile that Apple is not bending over backwards to provide free tools to Windows and Linux users? I think it's prudent of them not to waste money on such a small segment, some of which vehemently hate Apple. And when you talk about build servers you are still spending money on some machine to build your iOS app. You can get pretty good used Mac hardware if you really want to. For all those developers sitting on the sidelines refusing to develop iOS apps because they can't setup a build server on Azure, etc. Well, you're just making excuses.
I've been in computers since the early 90's and as far as I can see, Apple has always been hostile towards developers (and users).
> For all those developers sitting on the sidelines refusing to develop iOS apps...
I've made a ton of money building Ionic and Xamarin apps and recommend those to anybody building for iOS because both of them will let you spend as little time using OS X as possible. The way my workflow is now, I could totally rent a cloud Mac and just compile and publish stuff from there.
Anyway, even though I think OS X and iOS are quite possibly the worst operating systems I've ever had the displeasure of using and even though I know for a fact that Apple is hostile to developers and users, I don't mind making apps for them because I figure anyone who uses there stuff must not care about wasting money and it should be easy for me to grab some...and it is :)
And, like Spotify, all of my apps are subscription based with out-of-app signup, so Apple doesn't get 30% of my money. I also only buy used Macs because Apple doesn't get your money that way either. Right now I'm running a Mid-2012 Mac Pro with 32GB RAM that I got for ~$1,200. It was about double the money that I spent for a similar PC server, but I made all that back by taking money out of Apple's ecosystem and not putting it back in, so I feel like that's a win for everybody (except Apple of course, but hey - fuck them - if they're going to be hostile to me, I'm going to be hostile to them.)
[1] https://blogs.msdn.microsoft.com/interoperability/2012/12/21...