@ellenor2000 >Citation needed
It came to me in a dream.

Using the knowledge from the dream (and grep firmware -r), I found lots of proprietary software in the "Free"BSD source tree, with a few examples being:
https://cgit.freebsd.org/src/tree/sys/contrib/dev
https://cgit.freebsd.org/src/tree/sys/contrib/dev/iwi
https://cgit.freebsd.org/src/tree/sys/contrib/dev/nvidia

Although the proprietary software is encoded in a strange way, "Free"BSD is still distributing proprietary software and "Free"BSD is therefore proprietary software.

I also see a bunch of files that are unrelated to peripheral software with questionable licensing.