Correct, and that isn't what this article is talking about. This article is about an internal function in the OS that they've decided to is what they'd like to

Correct, and that isn't what this article is talking about. This article is about an internal function in the OS that they've decided to is what they'd like to use, and that the only reason they aren't using it is because it doesn't exist in older versions of macOS, because you know, it is an implementation detail of the OS. os_unfair_lock are a documented part of the OS API: https://developer.apple.com/documentation/os/1646466-os_unfair_lock_lock https://developer.apple.com/documentation/os/1646466-os_unfa...