Fair point, but Apple's growth is clearly in a decline compared to earlier years.

And once the established smartphone market stabilizes at something with Android clearly in the lead (like 80% Android and 20% iOS) which platform do you think will get the attention of developers? Which platform do you think will get the apps first? Which platform do you think will get the exclusive apps?

If (and I say if) the divide gets big enough for these kinds of mechanisms to trigger and start playing in, iOS as a platform will slowly but surely lose users, and have the process reinforce itself until the platform wither off and dies.

So in that regard, while market share isn't everything, it is still important for lots of other strategic concerns which most certainly are.