(According to wikipedia: All versions of macOS from Mac OS X Leopard to macOS 10.15 Catalina, except for OS X Lion,[68] have been registered on Intel-based systems, and all versions from macOS 11 Big Sur, the successor to macOS Catalina, to macOS 14 Sonoma have been registered on both x86-64 and ARM64 systems.)
Each OS release has to be separately certified for UNIX, it is indeed new for Sequoia.
Yeah this is misleadingly worded as if this is something new for Apple. They've been officially certified as Unix for 16 years now.
What’s new is a new level?tier? Of the certification that macOS sequoia has been certified for, rather than the overall Unix certification. [0]
[0] https://news.ycombinator.com/item?id=41698775
(According to wikipedia: All versions of macOS from Mac OS X Leopard to macOS 10.15 Catalina, except for OS X Lion,[68] have been registered on Intel-based systems, and all versions from macOS 11 Big Sur, the successor to macOS Catalina, to macOS 14 Sonoma have been registered on both x86-64 and ARM64 systems.)