[smoldesu]

MacOS has no use for it, I'll buy that much. But what about the automated calibration tools or QA software for displays and peripherals? I have a hard time believing that Apple doesn't have some level of internal testing firmware, because it certainly doesn't show up in MacOS. Much smaller companies do this regularly to test batches of production units for defects, it's part of the reason why custom firmware is possible to load on the Nintendo Switch. And Nintendo certainly didn't say "hey, use this", so I really, really have a hard time believing Apple did.