Earlier quoted context omitted.
Clean room re-implementations have stood up to many court challenges through the years, and are interoperability is explicitly permitted under things like the DMCA.
Yes, many clean-room reimplementations have stood up to court challenges. But many non -clean-room reimplementations have stood up, too. My argument is that it's neither necessary nor sufficient, just loosely correlated, and clean-room is not inherently a defense. And in particular, my argument is that it matters whether the communication between the dirty and clean rooms is a specification of an interface, or a desc…
That might be the case for interoperability with a hardware device, but you probably do to make an operating system that's compatible with Windows software and drivers, considering how historically brazen developers are at abusing internal details of Windows. Consider virus scanners that happily patch internal data structures like the SSDT, or other programs that detour a bunch of API functions, then expect those functions to be called in a specific order when a different API function is called, or programs that just reach into stack frames they don't control and pluck out values[1]. (There are some other good ones in that link.) Windows takes pains to be compatible with insane programs like this, so you could argue that copying weird implementation details like this is necessary for interoperability.
[1]: https://devblogs.microsoft.com/oldnewthing/20031223-00/?p=41...