We need FreeBSD the most because of both license and philosophy points of view, and Linux has still a lot to learn from the BSDs from a technical perspective, too.

The only thing that keeps me using Linux is that nowadays a significant portion of self-proclaimed Unix software is in fact mostly Linux software with absolutely no interest being compatible with other Unix systems.

And let me add that the community around BSDs are far far greater than any of the Linux ones I've come across.