Seriously? How much "diversity" and "innovation" do you need in terms of a charger?
It's not about the charger, it's about what the charger plugs into. Now, under this new regulation, all devices must accept the same input charge - regardless of whether or not a different charging system would be beneficial to the design. It's kind like specifying that all motor vehicles (from scooters up to eighteen wheelers) must use the same air filter. It'll be too big for some devices, too small for others, and lock designs ten years down the road to a standard written today.
Or, to put it another way, yes - charger designs evolve just the same as the equipment they're attached to. (Though chargers get far less attention because they aren't very sexy.)
It will also provide a wider window for cheap Chinese knock offs - and if you recall the debacle over counterfeit Apple chargers last year, you'll see why this can be a bad thing.