Free OS is the Problem
Quote from the article:
"Nobody outside China, except for Apple, makes money from making smartphones. Samsung lost a fortune last year. HTC has wiped out a year’s profits in just one quarter. And that’s when your operating system comes “for free.”"
Therein lies the rub. When both the hardware and software are commoditized, it gets awfully hard to differentiate your offering. Sure there are skins from different manufacturers but they are both pulled over the same system.
Apple's value proposition lies in its OS and the rest of the Mac ecosystem. Its hardware is just as much a commodity as Samsung's (arguably even more so) but they offer a substantially differentiated user experience that people are willing to pay for. While Apple is shameless in its pricing, their margins give you confidence that they will be around in 5 years to support the product and the ecosystem unlike me-too Android manufacturers (maybe with the exception of Samsung).
Samsung and HTC are facing the same problem that PC manufacturers have for years: the hardware is now good enough that people can get off the upgrade treadmill and not notice much of a difference from year to year. We've been there since the Galaxy S4 and it shows on the numbers. Marketing expenses are blowing up and it's getting ever harder to shift the inventory. The S6 is a solid build so that might entice some to upgrade. HTC is in the same boat.
Apple also has this problem. Now that their screen sizes caught up with the rest of the industry there aren't too many ways to make their next iPhone noticeably better than the 6.
Ditto for Microsoft although they should have enough exposure to this problem through their PC business. They are also religious about keeping their old gear up to date so when they will give me a reason to upgrade my Lumia 920 is anyone's guess. But based on my experience with Windows phone and MS' commitment of keeping everyone up to date with the latest system; the other manufacturers would have to make a hell of a case for me to switch to a competing platform.
The market has matured, now that the forest fire of smart phone adoption is dying down it'll be interesting to see how these companies keep up the volumes.