For me, free as in freedom is the primary concern. A proprietary programming language seems a bit ridiculous. I don't see myself paying for a programming language either, though. Libre and gratis are the norm in this space, so going against that sticks out in a bad way. It's like text editors and web browsers. We've had good free options for a long time. Anyone trying to push a non-free option might as well be giving out malware. That malware isn't appealing whether it has a pricetag or not.
As much as I don’t like it either, I can understand their perspective and actually believe that it might have been very hard to create and sustain such a comprehensive, thoughtfully and consistently designed language with an open source model. But it may be interesting to see if there are projects of similar scale with similar requirements that thrive (long-term) on a free and open source model.
This! I am coding something right now that Mathematica would honestly make 100x easier, but I refuse to use it because I want my software to be FOSS, and not depend on a proprietary language.
I respect Wolfram's enginuity, but I resent his ego for keeping us all out of his walled garden.
