Actually, the biggest problem is his confusion of free (as in price) with cost-less. Nothing is or can be cost-less, but that has little to do with the price charged for it.
I think the implication is that "free" is being quoted from elsewhere and the author doesn't necessarily agree that it is without cost just because such cost is not denominated in dollars.
I doubt that he is going for wordplay. Rather, he is trying to convey that it's not the price he is talking about when he says "free", but "freedom". And it's a simple example that makes the distinction and sticks. Maybe he should've called it "Freedom Software"?
Sure, if for some reason you want to take the most absolute, most pedantic definition of the word 'free' and you are utterly confused by it meaning something else then, yes, it is not free.
When I read this article, it remind me how english have a problem with the semantic of the word "free".
When he says:
"this photograph is not free"
he means :
"this photograph has a cost"
when I understand:
"this photograph has a licence witch does not allow people to share, copy, modify as wish"
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