My understanding is that the LED is hard-wired the power source of the camera sensor. There's no separate software command to turn the LED on. All Macs run Wind

My understanding is that the LED is hard-wired the power source of the camera sensor. There's no separate software command to turn the LED on. All Macs run Windows and most run Linux pretty well. So you /could/ audit at least one open source software implementation. However, like many others have mentioned in this thread, personally I see the value in having a physical cover in addition.