[comex]

It's not like every other popular language doesn't include huge rich sets of free libraries and algorithms - Mathematica has few good competitors (not none) in many math and science areas, but competitors are obviously much richer in most of the rest (which is important for a general purpose programming language). It's just that those libraries are usually spread among many open source libraries written by different people rather than being all centralized.

Based on an accounting of the work involved, it's reasonable to charge, but based on the options available (and the relative unprovenness of the Wolfram Language), it's also perfectly reasonable for people like the parent to insist on free languages only. It's what Wolfram's competing with, at least in the view of the world where it's not singlehandedly "redefin[ing] the process of programming"...