I'm not even sure, why this blog post was necessary in the first place. No one argues that a company needs revenue to pay employees and WRI is trying to maximize its profit. That is absolutely fine. However, claiming that OSS cannot achieve great and well-designed software, just to cover the true reasons is simply wrong. Maybe someone should remind WRI that they use Qt, Cairo, Pango, OpenCV and many more OSS libraries under the hood. Qt, in particular, is almost as old as Mathematica itself when the information on Wikipedia is correct.