But I needed a Linux VM and somehow I couldn’t get the hypervisor to work with anything but BSD

Do you know about the linux-compat layer on FreeBSD? https://docs.freebsd.org/en/books/handbook/linuxemu/

I also wish debian GNU/kfreeBSD was still a thing.

I just think a majority of people do not care about which OS they use, or even know what is an OS. The only way for GNU/Linux to become big is if companies start shipping it in computers instead of windows.

OSX also came from NextStep which came from the original BSD Unix. They used FreeBSD as well. OSX is also certified Unix starting from leopard. This year apple did not renew the certification, so later releases of macOS are not Unix, but Unix-like.

Linux is the second-most popular descendent of Unix, the first being OSX.

Linux is not really a descendant of Unix. It is a Unix clone, but its roots do not trace back to Unix.

templeos is public domain, which is incompatible with open source

Where did you come up with that conclusion?