Look a bit further, why don't you
The explosion of OSes for handsets is a characteristic of every upcoming market. If you would look a bit further you can see the same thing with video recorders and, especially, automobiles. Eventually a market will settle on a small number of major players, each finding their proper niche.
Personally I don't think Android will rule the roost come 2030. For one very simple reason: nobody wants it. Google really doesn't care about Android apart from a tactical weapon to ward off Apple in the entertainment sector. Handset makers don't care about Android and are doing their best to differentiate themselves from the competition. Users don't care (apart from the zealots who will decry I'm an idiot), they just want a smartphone that's not an iPhone (for whatever reason: cost/carrier/lack of style). Carriers don't care, except they will, once Android assumes your analogy and will give birth to Android Windows with all the viruses and malware that go along with it.