"NextBSD" was first released in 2015:
* https://en.wikipedia.org/wiki/NextBSD
Over a decade after macOS/Mac OS X was initially released:
> macOS (previously OS X and originally Mac OS X) is a proprietary Unix[7][8] operating system, derived from OPENSTEP for Mach and FreeBSD, which has been marketed and developed by Apple since 2001.
* https://en.wikipedia.org/wiki/MacOS
> Darwin is the core Unix-like operating system of macOS, iOS, watchOS, tvOS, iPadOS, audioOS, visionOS, and bridgeOS. It previously existed as an independent open-source operating system, first released by Apple in 2000. It is composed of code derived from NeXTSTEP, FreeBSD[3] and other BSD operating systems,[7] Mach, and […]
* https://en.wikipedia.org/wiki/Darwin_(operating_system)
I remember reading release notes for FreeBSD in the '00s and seeing the exact same lines in the release notes for earlier versions of OS X.