I don't think this is necessarily true. Yes, people leaving for keyboard-feature reasons are power users. But there are other keyboard reasons.

For example, iOS7 totally broke the keyboard so that fast touch-typists just can't type on it any more. This doesn't matter on something small like a phone, but on an iPad it is super-frustrating. Apple fixed it somewhat in recent updates but it's still broken in a few basic ways, all having to do with the fact that the person who programmed the new keyboard doesn't know how typing works.

It is confusing enough that a non-power-user probably doesn't have a clear idea why typing sucks now, they just know that letters don't come out with the right capitals any more, sometimes extra spaces show up, and damn that shift key is confusing. etc. It is not so much "Android is better" as it is "iOS is not a nice experience any more".

There are similar things to do with web browsing. Web browsing is supposed to be one of the few things these devices specialize in, but on my iPad Air it is terrible. If I go to a web site with images on it and scroll down, most of the images don't load for a LONG time, leaving me with mainly a blank page. When iOS7 came out the browser crashed all the damn time. Now that is mostly fixed but it still crashes sometimes.

Meanwhile there are all these timing-based gestures that are thrown off by browser performance problems, leading to bad user experiences. For example, I want to scroll down a page, so I press on the screen, drag, and release. Well oops, some piece of JavaScript ran right then or something, causing the browser's timing to get confused (maybe it counts frames and only a couple of frames went by), so instead of a drag it interprets this as a tap, which for some reason causes me to select some garbage on the page that I don't care about. Well now I am in select mode and things get only more confusing from there (especially if more performance hitches are happening). This happens all the time.

When you can't even scroll down a web page reliably, and yet that is one of the main use cases you are selling your product for, you can't claim it is a luxury product. You aren't delivering a luxury experience so you can't charge a premium.

Apple has gotten away with this in the past, in similar situations, though, because of newness and shininess. As Marc Andreesen pointed out recently, for the first few years you could barely even make a call on an iPhone, and when you did it was super-frustrating. But still it caught on. I think this is just because it was so new and exciting and there weren't real competitors yet. Once the bloom is off that rose, in order to be perceived as a premium brand, you have to actually deliver quality. But Apple is not delivering quality with the OS, they are just delivering some kind of skin-deep attempt of an appearance of quality.

I consider iOS7 to be a huge misstep and a giant missed opportunity, much bigger even than Siri or Maps. I am not sure if fixing iOS7 would solve all Apple's problems, but it is where I would start.

However, I don't think the thesis of this article -- lack of UI features -- would be my first step. Because I don't agree with the article that iOS 7 is simple. In reality it's a mess, it just tries to appear simple. So the first step is making it really, actually simple, and make it deliver a solid, quality experience. Then you can think about adding UI features, which I would claim people don't care about as much.