I strongly doubt it. It'll be another two years before we start to approach saturation in the worldwide smart phone market. Apple's going to keep selling even more smart phones, and hauling in even more money. It's also still early to really know where tablets are going to go and what the potential market is there. Will they eventually take over most of the PC market? Hard to say what the potential is there. Apple is also continuing to sell more and more desktop and notebook computers (Yeah, they still make those ) so they're still slowly growing there as well.
People make this same argument every new product generation and it turns out not to be true. Eventually the problems get fixed and no one really cares about them or the tech press latches on to some new sensationalism to drive page views and stop writing about whatever latest -gate scandal is plaguing Apple and will spell their doom.
Given their past history, they seem to be pretty good at fixing problems and getting things smoothed out. Of course they'll run into some new problems on the next go around and people will jump all over that as though it somehow spells doom for the company.
That's what happens when you completely tap out your existing market and don't grow into anything else. That's why Apple isn't going to have any problems for at least another two or three years. Their two biggest markets are still growing rapidly year-over-year. When they get their, they'll need to find some next big thing for the company if they want to keep expanding.
From experience, things quickly get to where you have people quoting one or two words, and the context is completely lost when you break it up like that, so...
In those emerging markets, it's the low cost Android devices that are hoovering up the new customers. Not the high end boutique products Apple sells. So, Apple's market is basically self-limited to just the people who can afford their inflated prices in the name of a healthy profit margin. Nothing wrong with a healthy profit margin, but it's going to be a tough sell for Apple. They have to convince people that they should ignore the much lower cost Android device, that can do pretty much everything the iPhone can just maybe not quite as "slickly". When $100 might be over a month's income, I don't see that sales pitch going over very well.
And I'm sure people said that RIM and Nokia have nothing to worry about. Every time BIS went down, they eventually fixed it and no one cared. Every time someone has a call dropped by AT&T or the LTE network for Verizon goes down... They eventually fix it and no one cares. Do you have any interest in bridges? I have a couple beauties for sale! Real cheap! Recently de-trolled even!
The larger point, however, is that the mainstream press was considerably more muted this time around. So what happens if the next time around most of the mainstream press decides that they're tired of covering yet another iPhone release and just ignores it? You still think there will be lines around the block? Or maybe they don't ignore it completely, but they just give it kind of a cursory bit of coverage.
Also, Apple has apparently decided to make a number of decisions that compromise quality. Their retina model laptops have virtually everything integrated into the logic board now, the display panel is quite a bit more fragile now... Which is all kind of again missing the forest for the trees, as Apple has been systematically winding down their computer division for a while now, so then they will just have the iDevices left to keep them going. Will they be able to find some other market to expand into before that comes crashing down around them? Who knows. Steve Jobs was the one who had a unique talent for taking other people's ideas and packaging them in such a way that would sell very well, and now he's dead. Sure, there's no way he could have been singularly responsible for everything, but he was the one who would green light ideas. Tim Cook is a operations and logistics guy, not an idea guy. It'll probably be like when Jobs was forced out, and the guy to replace him tried to do everything exactly the same as Jobs, but things still came crashing down around him.
And then at the end, it seems as if you agree with my premise, but were arguing with it for... Reasons. The iPhone 5 will probably be considered a success in the short term, even the mid-term... But when the company is desperately clinging to life like RIM and Nokia, and people look back with the benefit of future knowledge, I'm betting this will be the point where they say things started to go off the rails.