Its a catch 22. Its also a reason for untimely updates, and MAJOR fragmentation. Also no control over hardware performance.
Honestly I have been a Android supporter since the G1, but the older I get and more Im with the phone, the things I stated above are starting to bother me so much that Im looking at iPhones.
Other manufactures could still produce their skinned phones, and offer different hardware configurations, but Moto could ne Nexus everything and offer a verity of phones with different features and price levels.
Also unless Samsung and HTC are willing to be exclusively Android(which they wont), I think Google SHOULD go forward with that plan, and Google has no promises from them for long term.