Yes, pinch to zoom is possible with one hand, but awkward. The same is true about reaching some parts of the screen with your thumb, so iPhones etc are actually made to be held in one hand, while being operated with the other.

That's why the N9's focus on improving one handed use is a pretty big deal in this class of phones. As for your other questions, the simple answer is, that it's hard.

There is a pretty big gap in terms of product design between the N9 and the current iPhone, but there's an even bigger gap after that. If you refuse to buy Nokia or Apple out of principle, that is just something you have to live with.