Well, and my GUI editors don't respond to single-letter commands. It would violate my expectations of their UIs if they did. Similarly, in vim, I expect ctrl+q to send an XON signal to my terminal emulator...not to quit my editor.

They're different programs with different UI conventions. I don't expect them to act the same. And I especially don't expect vim to change, after having 25 years of its own precedent and an additional 16 through vi.