"that price is vastly out of proportion from the cost of providing the software"
That's just an unfounded assumption by the author. He says he knows this, even though he doesn't know how many developers are working on it, what they get paid, how much time each release takes, how large the code base is, or how many users the product has. Essentially, he has made up a cost in his head, and decided that the costs must be less than his fantasy. For all we know, he's one of 2 users, and the cost for keeping his editor available is $100k/yr/user.
This also completely ignores the fact that prices for software aren't generally set using cost plus pricing.