kohlrak: In theory it should ...
NovumZ: What kohlrak said, yeah!
Theories are great, and I too would love to live in an ideal perfect world.
That said, we both know it doesn't quite work that way. Sure we can write a "Hello, world!" in C++ and it will work on nearly every system there's a compiler for, but for complex software, such as games, it's nowhere near that simple. Cross-platform games require tremendous time investment, and time investment is money investment.
Why do you suppose Witcher 3 wasn't released on Linux? Is it because:
a) it would cost a lot to do that, or
b) the devs just didn't really feel like it, plus they hate Linux, or
c) it's a conspiracy between evil corporations, evil oligarchs, the evil Illuminati, and evil Rothschild personally