I doubt it:
- Owners of Android handsets on average have lower disposable income than owners of iOS devices. On top of that, a lot of Android phones are in developing countries.
- Most Android handsets run an old version of the OS and will never be updated, thus limiting the choice of APIs that developers can use.
- Many Android handsets are used as dumbphones, their owners will never download apps.
- There is not one main app marketplace for Android, and not all Android users can use the same marketplaces.
- Few Google Play accounts have credit cards linked to them. Amazon is in a much better position, but Apple still has more credit cards on file.
- Google makes developers pay for chargebacks.
For this increasingly dominant app category reach is what counts.
I haven't seen any evidence of Apple's App Store revenues dropping markedly. Pretty sure the market would be VERY concerned if that were the case.
Remember though, most of the developers who are doing work that actually matters on mobile aren't doing it because they want do, they're doing it because a corporate strategist thought it would be profitable use of their time.
An iOS app I'm working on right now has been a nightmare in comparison because we had to port our layouts to the i5 form factor but can't require iOS 6 just to get autologous. Apple really blew that transition.
Also, you can say that the API level differences don't matter because they are hidden by compatibility libraries like The Support Package, but the truth is that those are just the newer APIs re-implemented against the old interfaces. You pay for that extra abstraction with wasted cycles and bloat, and it's an ugly solution. Even still, those libraries aren't perfect: there have been subtle bugs or incompatibilities introduced by their use which are notoriously hard to find. Finally, even if the newer APIs are present on the device, The Support Library will still be used (last I checked, though I think they are working on this).
Less objectively, it's a matter of preference. Some people just prefer objective C to a JVM compilable language.
The emulator is atrociously slow and every manufacturer seems to have different implementations of UI controls meaning it is expensive and time consuming to test.