It's niche enough to not justify the hundreds of millions of dollars such a project would require and the high risks. OSX "just works" because it has a full su

It's niche enough to not justify the hundreds of millions of dollars such a project would require and the high risks. OSX "just works" because it has a full suite of software that comes loaded on it and "just works" very well and makes a lot of Windows programs jealous (except for some Office products). If people want customization and general freedom, they already have Linux for free. I think it is safe to say that the market for people unhappy enough with both OSX and Linux, and willing to pay for that, enough to justify years and years of expensive and risky development, is _relatively_ small.