Not sure why everyone is stuck on "from scratch" part. This is from scratch in all practical terms to me. They would be wasting their and viewer time if not done this way.
Because there are us who have actually done USB device drivers "from scratch", i.e. using the specs or gone through the RE process for an unknown device, while this is basically porting existing code to a new API. Thus it's rather clickbaity.
Sure. But writing drivers via specs is also almost also porting :)
"From scratch" is not interesting or generalizable. Chatgpt can do that, infact I have used GPT to write IMU driver "from scratch" by just giving it a bunch of datasheet pdfs...
