I doubt that would help. Some developers do the tests but aren't very good at testing. Others wouldn't do the tests but would copy and paste a long list of "tested devices", and with two million apps, you would never be able to tell the former cases from the latter.
Google could probably address this more effectively with some variant of: dev technologies making it easier to design for varied hardware profiles, test suites in the simulator that automate many types of testing across a set of standard profiles, specs for hardware makers showing them what the requirements of each standardized profile were, extensive test suites for hardware makers to make sure they conform to a standard profile, and a Google certification that a given device matches the such-and-such profile in all respects, so that if you test your code against the such-and-such profile in the simulator, and it works, it will work on the certified device.
There is less incentive to polish on even one device when you know it's <1% of the market. Seems better to put more effort to get it running reasonably well on more devices.
You would think they would at least polish it on their primary device.
I think there's a cultural difference between the two platforms as well. The developers that are inclined to want to make their application perfect and beautiful seem to be attracted to iOS.
Google could probably address this more effectively with some variant of: dev technologies making it easier to design for varied hardware profiles, test suites in the simulator that automate many types of testing across a set of standard profiles, specs for hardware makers showing them what the requirements of each standardized profile were, extensive test suites for hardware makers to make sure they conform to a standard profile, and a Google certification that a given device matches the such-and-such profile in all respects, so that if you test your code against the such-and-such profile in the simulator, and it works, it will work on the certified device.