Linux audio is at a critical juncture that is similar to a band which has
been together for several years that has written great songs but hasn't had
a 'hit' yet.
In my opinion, Linux audio is a hit. 5 years ago I finished secondary school and decided to try learn "audio programming". I'd already dabbled with C++ and Python for a year or so. The reason that I'm where I am now w.r.t. audio coding is due to the open, helpful and sharing attributes of the LAD / LAU communities.
Perhaps when comparing Linux audio to other OS's on commercial aspects things look skewed: but you've already discounted one fantastic aspect of Linux audio, and that can't be said for proprietary land where the best features are the most gaurded.