This is a really, really good point -- and is a result of the model of Linux being only a kernel (and not system libraries, commands, etc.). It means that any real use of Linux is not merely signing up for kernel maintenance (which itself can be arduous) but also must make decisions around every other aspect of the system (each with its own communities, release management, etc.). This act is the act of creating a distribution -- and it's a huge burden to take on. Both illumos and the BSD derivatives make this significantly easier by simply including much more of the system within their scope: they are not merely kernels, but also system libraries and commands.

This weighed heavily in our own calculus, so I'm glad you brought it up!