You're very emotional about it, but yeah, that does ring true. If the app support was there, I'd probably use Windows Mobile much longer than I did. I still prefer it over Android or iOS, but low market share and lack of developer support killed it.
But it's kinda chicken or egg situation - even before it lost majority of app support its market share was quite low.
As for the Mac vs Windows... it's a different ballpark.
Windows is the default desktop system with a majority of market share, BUT that includes not only creatives, but also everyone from accountants and gamers to soccer moms just harvesting virtual tomatoes on Facebook.
And you can't throw a MacBook without hitting a creative of some sort. Total market share is much lower than Windows, sure, but what share there is is basically your target audience.
As for Linux sure, this thread is a proof there are creatives who want to use it. But we're still like 1% of 1%.