Comment by mjg59

_OS is basically irrelevant, _OSI has been used for over 20 years now. The right way to think about the values the OS presents to the firmware is in terms of a contract between the OS and the firmware in terms of mutual expectations. Windows effectively embodies a contract - the behaviour of any given Windows release will remain constant. There's no way to define an equivalent definition for Linux (because Linux's behaviour keeps changing to match hardware expectations), so it makes more sense for us to attempt to mimic the stable contract Windows provides (and it helps that that's the contract that the vendor has tested against in the first place). I went into this oh good lord over 15 years ago: https://mjg59.livejournal.com/96129.html