That's like suggesting that Mercedes Benz have lost already to Ford because they have smaller market share. Apple produce a premium product with prices and margins that reflect that. Of course they would prefer dominant market share, as would Mercedes. But a non-majority share does not imply that they've somehow lost.
It's like mercedes, only mercedes also gets to drive on nicer roads that go more places.
When market share translates to usage and developer revenue, as it may some day, this will change. But network effects scarcely reinforce your point.
Maybe this won't continue but if you're skating to where the puck will be then it doesn't look so much like Apple right now.
Which they have, when you're talking about market share. There's some cognitive dissonance going on here- Windows Phone can't succeed because it has a low market share. But Apple succeeds because it has a low market share.
Basically, if low market share isn't a problem for Apple, there's no reason why it would be a problem for MS.
There are still millions of iPhones sold every year, even if they're a smaller piece of the overall pie.
Contrast to Windows Phone which never had any kind of market share or importance, and has to fight up from absolutely nothing.
That's the difference between iPhone's small market share and WP's small share.