That's still directly tied to the control inputs. Just the TYPE, not the number. This was the same conflict in gaming transitioning from the late 80s to the early-to-mid 90s when joysticks stopped being popular and mouses started working as intended, freeing up a hand to stay on a keyboard. Games relied more heavily on binary layouts rather than contextual inputs from the joystick (which has resurfaced to some degree thanks to controller analog sticks) and they were creative in their utility due to the limitations of those inputs being binary, yet so potentially numerous. Nowadays controllers do offer a few things that the keyboard and mouse do not (namely pressure-sensitivity inputs), but the major difference is still the number of inputs. The kinds of inputs don't have nearly as much of an impact, though they do HAVE an impact, as you expressed.