To play devils advocate here:
Taking GPL code into your product and selling it, the fact of selling your product is not harming the person who wrote the GPL code. But with GPLed code RMS has a totally different view than with pictures of nude children.
I can imagine reading an rms essay on how coming into my yard and taking my ladder without permission, using it without damage, and returning it before I noticed it missing imposed no harm upon me, so the taking of my property was not wrong, though the ongoing possession would be.
To your later-added devil’s advocate paragraph: rms is fine with you selling a product that includes GPL code and as far as I can tell always has been. What he’s not fine with is you imposing restrictions that prevent someone that you do sell the code to from effectively modifying or further sharing that product.
Nothing in the license precludes the sale of such a combined work though, as in your devil’s advocate query.
I’m not even sure where the confusion or disagreement is in this sub-thread to be honest. The license is short and fairly clear; there’s ample additional “what does this mean for inclusion of GPL code in commercial products?” FAQs and a fairly large body of commercial products openly marketed which include GPL code in them.
[0] - https://www.gnu.org/licenses/gpl-faq.html#GPLCommercially
In your scenario, the user won't have access to the code they'd need to modify the product you sold them. That is the harm the GPL is designed to protect against.
I read that he’s intending the extremely literal meaning of “having” as he often takes extremely precise, literal meanings that make his writings more difficult to understand than would otherwise be.
Let me be clear: I’m not in any way supporting child porn, but I can see how rms could hold a view that merely having a specific sequence of bits that can be displayed as a picture does not harm anyone.
Perhaps someone was harmed by the circumstances under which the picture was taken. Perhaps some ex- is harmed by the thought that you might have that photo. Almost surely allowing the purchase or trading of such pictures encourages future harm. There are lots of reasons to oppose child porn, but rms is, for reasons known to him, choosing to argue that, in a very literal sense, the passive having of the bits is not among them.
Context: I’ve read a lot of rms writings and worked for FSF as his typist for 9 hours back around 1990 before I quit. (I wish I’d have been able to do it longer, but it wasn’t worth the $10/hr to listen to rms dictate keystrokes and enter them. I would frustrate him as I was trying to learn what the keystrokes were doing and he just wanted me to type faster. When I told him I was quitting after the third three hour session, he graciously offered that I was just getting fast enough to not be frustrating, that most people quit in session 1 or 2, and he’d make sure FSF sent me the $90 which they did.) I don’t consider myself to have a particular “side” here, but if my minor interactions with him are relevant to anyone, I wanted to disclose them.