The technicality being that Darwin seizes to be an open source operating system once it is shipped with closed source components. Why would this be true?
OK here we go, and why not, after all it's Sunday and I've got nothing better to do.. right?
The central tenet was that discourse here is regularly devoid of sound engineering because it tends to be blinded by mindless cultural perceptions of the companies involved in whatever happens to be under discussion. In the case of Apple the expectation is their products are flawless and if not then all hell will be paid on blogs and comment sections everywhere.
Whether or not Darwin is or isn't open source doesn't freaking matter, it was heavily marketed as such back in the sands of time and even if this wasn't the case it doesn't invalidate the central point made in the rant - that just because this device has an Apple logo every popular discussion surrounding it turns to mindless diatribe as a result of non-engineering centric expectations people place on their products, and every engineering-centric party (i.e. hackers) must deal with the whining polluting engineering-centric forums for days every time it happens.
In effect, the complaint is that commenting resembles the squabble of a throng of uninformed consumers rather than the judicious discourse of a forum of engineers.