top(1): "Command not understood"

Oh, tobic, that's interesting! I also noticed some commands with options that had no effect at all. I assumed the documentation was out-of-date, but it turns out that it may also be out-of-this-world. ;)

Turns out that has the man pages of multiple operating systems not only FreeBSD's.

Wow, that's unexpected. Does anyone know the decision behind this move?

IMHO this makes the FreeBSD learning curve unnecessarily difficult. Imagine someone wants to learn about the system and then surprised why the man pages don't seem to work. Quite confusing and uncomfortable. Seems like I'm also not the first person who's been bitten by this.