This is like a Wii fan arguing that lazy developers don't push the system. No one on earth disagrees, but it's better to treat the symptom when you know the problem isn't going to change. Better hardware would lead to a better user experience for more people.
WP7 has a lot of momentum against it. Even if it was manifestly the best phone experience, people would still be hesitant to switch to it. Making it easier for them to say no by having the hardware lag behind everyone else's, or fucking up the subsidy / hardware pricing so that single-core WP7 phones cost the same as the Nexus Prime or iPhone 4S only serve to ensure that the platform is less successful and thus receives less support.