I fully agree that with Android share we are moving to PC-Mac situation, but in smartphones.
However, guess what? It is good for Apple because it can maintain its margins and be profitable.
Remember how things ended for PC companies like Gateway, Dell, IBM and even MS, though it still charges obscene amount of money for its OS and Microsoft Office. Most of them exited market as they won't making money at all.
Apple makes a market popular, gets the lion's share of profits, cedes the profitless market share, moves to another lucrative market and gets lion's share of profits there. This Apple cycle is a masterpiece now that the company has mastered services to turn them into one of largest money making machines in the world (Forbes 100?), it is now can even thrive using just revenue from services, even with less profits from hardware. Of course, beautiful hardware is a key to that success, both Macs and iOS devices, for which Apple also receives money