I sure hope that they don't have that mentality, because they have promised something now that they can't seem to give us an official answer for. I honestly don't see the big deal when they already seem to have coded OpenGL into their engine. Once the engine work is done there isn't a lot of extra code needed in the game.
It's strange how some AAA developers try to give the impression that developing games natively costs a lot of money and time. I don't think this is true because you see a lot of indie developers who will gladly develop a Linux version, and they don't have this attitude where they make it seem so hard. Many of these indie games are also pretty complex, but that is really besides the point, because I think the only thing you need is to separate the graphical rendering to use OpenGL or some other Linux compatible graphics renderer.
Do you guys know of a game called Neverwinter Nights? It has a Linux version. The game is fairly complex, actually I think it's very complex, and I don't think I ever heard Bioware complain about how hard it is to develop a Linux version back then.
I think that companies either don't want to get on Microsoft's bad side, so they get more support for development on Windows & Xbox One, or they are simply bought out by Microsoft. This is a wrong approach though, because they should use companies like that to get knowledge about a piece of hardware. They should instead find someone who is not associated with such a company to do the work.
This really strikes me the wrong way, because I am a person who believe that a person should always keep his word, but of course within reason, because we all make mistakes, but it seems to me that so few value honesty. Recently I've come to question CD Project Red, because of this and the Xbox One Collector's Edition bonus.
If they don't make a Linux version I will consider boycotting them. It all depends on what happens afterwards. If we get no Linux version and they don't give a sincere apology for the Steam mess then I will boycott them. Because this would mean that they don't care for their customers like they claim and used to.