Just lock down the OS so we can send a reliable signal whether the click originated from a real hardware input device or was software-driven

Oh, you programmed your Arduino to present itself as a mouse via USB, so you can do automated click-fraud that way? No problem, only certified hardware allowed as input devices from now on

I'm not sure what we are going to do about robot arms using touchscreens, or little devices that trick mouse sensors into thinking it's moving. Maybe continuous fingerprint reading?