That just shows a lack of knowledge of the quantinty of commercial OSes available out there.

Were are the volunteers for Sony and Nintendo console OSes, Android, ChromeOS, Fuchsia, IBM i, IBM z/OS, INTEGRITY, QNX,Unisys ClearPath, Solaris, HP-UX, Aix, vxWorks.....?

Both PS Vita and Nintendo Switch have miles long credits listing all the licenses (mostly BSD) and authors of the many OSS software bits they use.

Indeed and almost zero contributions to upstream.

Those listings are required by the license.

Also they aren't Linux or BSD derivatives, rather their own OSes.

Yep, exactly - IIRC Sony did some code drops to FreeBSD long ago improving SMP performance but that was preatty much it.