Even if it cost them a fair amount of money to port it all over, they're Apple so they have the money in the bank. Plus I can imagine the ROI would be fairly significant when you consider how many more people could get into casual iOS development and then potentially make it into a full time thing.
Xcode and the entire stack behind it do not run on Windows or Linux. It would take a team of engineers months to pull it off, then another team to continuously support it. In those months, the feature set of Xcode and the compilers will have improved again and there would never be a stable version for a different platform.
Porting Xcode to Windows or Linux would probably be the worst idea Apple ever made.
Whilst I'm sure it's not a trivial task something tells me that there is more to this than technical limitations.
Apple doesn't need to port their software to Windows or Linux at all but simply allow to use OSX in an emulator. Even this is forbidden by Apple (it's not a surprise).
I think it was a huge mistake of Apple to allow iOS development on Macs only. If they hadn' make this mistake almost all people would develop for iOS mobile devices now, and Android wouldn't have had any chance to win. In some sense Steve Jobs himself was the main reason that Android became so successful :-)
> In addition, the cost of a Mac for development ($599 for a mini) is not stopping anybody,
It has stopped me. I have a pretty good PC, and I never accepted that I would have to buy an additional Mac solely to fed my iphone. It's a waste of room and money. For that reason I use Android.
Personally I have a pretty close and loving relationship with my workstation. That's why it needs to be a laptop.
I can't stand being tied to a physical location and working through remote desktop is too painful to bother, feasible if something is burning, but not otherwise.