I think it's the people saying that Android is not the Windows of smartphones that will be considered crazy at this point (unlike before when it was the one saying it who who were considered that).
If Apple wants to start selling $100/$200 phones (they dont) there's no "compatibility" barrier stopping people from buying them.
If a new free licensed OS comes out based on some radically innovative tech (mind control? whatever...) those factories won't blink at switching over.
If the Chinese government decides to outlaw Android because the nephew of the Premier runs a competing company/whatever... well some people will complain but most will just buy whatever the next best option is.
Now there's no scenario for Android tanking that seems very likely to happen to me so ... yes I'd expect Android to dominate market share going forward. But that's a huge difference from Windows, a monopoly that didn't care what anyone expected to happen. Resistance was futile.
Google doesn't sell Android of course - they ride it. It's a completely different business model that can't be compared to the business model of selling packaged retail software.
What Android does, by spreading development costs across the whole market (and beyond - since Android is Linux it leverages resources spent on refining it for uses other than mobile devices), is allowing device manufacturers to build good phones in shorter cycles for prices lower than they would otherwise be possible.