I'm gonna have to challenge you on that 100x number because I think you may have plucked it from thin air. Obviously contributor numbers are a) hard to define and b) hard to capture, but for an order-of-magnitude estimation, I give you two sources, both of which have incentive and access to maximise the number counted:

1. Linux. "Over 13,500 developers", https://www.linuxfoundation.org/announcements/linux-foundati...

2. FreeBSD. I make this a little over 2,300 names: https://www.freebsd.org/doc/en/articles/contributors/article...

So I suggest it is a only a 6x difference, or at least in that vicinity.

I imagine that the column inches go overwhelmingly to Linux, but tech journalists are moths to a flame.

https://lwn.net/Articles/708266/ -- 1,719 in a ~ten week window.

https://svnweb.freebsd.org/base/head/ -- 128 individual developers have committed to FreeBSD head in the last ~ten week window. (svn log http://svn.freebsd.org/base/head |egrep '^r[0-9]{6,6} \| ' | grep -B999999999 2016-11-25 | cut -d" " -f3 commits.log |sort | uniq | wc -l)

So Linux has more like 13x individual developer count in recent times. You can round that down to 10x if you like, but 6x doesn't tell the recent story.

Note that this is comparing the Linux kernel to FreeBSD base, which is like kernel + glibc + coreutils + binutils + other stuff.

Mindshare is not a zero-sum game like market share, so scope of function is irrelevant; and is not a short-term phenomenon, so ten weeks is nothing.