>>12026584
Part of the blame falls on Microsoft. Their USB gamepad API for Windows does not allow you to have any more inputs than what is on Xbox360 and later controllers. Two analog sticks, one d-pad, two digital shoulder buttons, two analog shoulder buttons, a start and select. That's it.
Want to add a third analog input option?
TOO BAD!
Want six face buttons?
TOO BAD! unless you just move two of the should buttons as face buttons
Want six shoulder buttons?
TOO BAD!
Want a touchpad, or any other additional feature?
TOO BAD!
Microsoft basically set the layout of their controller in stone as the max inputs you can have on a gamepad in PC without resorting to 3rd party drivers that can break all sorts of compatibility. That's why any controllers that do have extra buttons are either just auto/turbo buttons, for recording macros, or for just cloning an existing button to a new location.