IMO the reachability gesture improves about 20% of situations where one more tap is required, and for all the other situations I find I need more than one tap.
I would say my usage is inverted. 80% of the time it's one-tap; however, of that 80%, 90% is just hitting the back button. Move the back button to the bottom where it's reachable with one hand and ~75% of the use case for reachability is solved (for me, at least).
