ouchqt

My understanding is that apple officially changed from OS X to macOS in 2020 with the launch of macOS 11, even though the branding changed a few years earlier.

Yep, IIRC Havok’s licensing explicitly disallows redistribution of their technology, including headers and pre-compiled binaries.

Source 1 is a good example here, where licensees of source need to also obtain a havok license before Valve can give them any code.