I find it amazing that this argument still continues. Probably the only reason it still continues is because people in general don't remember history. Most never cared to learn it, most were deluded by promises. It all repeats
(some history rambling self-censored)
It is enough to note, that Apple never looked at "Linux" being the foundation of their next generation OS. That would tell a lot. Hardly anyone will buy it, that MacOS X is difficult to learn.
Linux even after so many years continues to be bunch of kludges, without well defined architecture. It may work for users, much as Windows does, but I fail to see how it would appeal to any admin.
It is true, that there is software for "Linux" that is not available for FreeBSD, but this is because of the licensing. Let me clarify it:
If you are an vendor, that has a piece of code, whatever. If you release it under the GPL license, none of your competitors would be able to use it to create competing product. They will have to publish their modifications and additions as well. Thus, you are preventing your competitors to build on your work. Perfect for the large companies, eh?
With the BSD and compatible licenses, once you publish it, the code becomes public. Anyone may do as they please with it, as long as they give due credit. Your competitors may take your code, add to it, fix your bugs, keep parts of their modifications for themselves. It was demonstrated many times, that for a software developer it is stupid to hide the code, because bugs stay undiscovered.
But this is all matter of choice.