This position sells the opposing argument short. It's not so much "designers believe a priori that Android users won't pay for good design," it's "Android users have a long and well-established track record of not paying for good design." People are still experimenting, and I think that this is actually a case you can rely on market mechanisms to handle. If Android users start demonstrating a willingness to pay for good design commensurate with the difficulty of producing good design for Android devices, there'll be a market opportunity there. Someone will get rewarded for providing people with what they're willing to pay for.
This leads into how Bowles sells the other argument short: he conflates design and graphic design when he address the "Android is hard to design for" argument. Design is, to borrow a famous phrasing, how it works. Sure, it was tough to do good graphic design for Gingerbread and it's much easier now. Great. However, the fragmentation and glacially-slow upgrades have a real cost here - to design the same functionality, may require spanning multiple API versions. The comparison to the diversity of Web browsers and viewers doesn't work because that diversity, relies on web standards. The equivalent of web standards that would allow an Android app to do responsive design in the manner of a web app, devices don't have or respect.
Fundamentally, it seems like Bowles doesn't get that the answer to his question is "because doing good design work on Android is more expensive and people pay less for it." Sure, you could ask designers to make speculative investments in Android, but I suspect that'll go about as well as asking people to make speculative investments of their professional time and skill usually goes. Professionals who respect their own time and worth, go where they can do good work and get paid well for it. Currently, that means they don't go to Android.