This is a strange interpretation of the word 'free'. If you mean 'gratis', it definitely is free of charge. If you mean 'libre', it is MIT licensed, so you can do whatever you want with it. If you mean some other kind of 'freedom', you should probably clarify...
I think the parent's point is that you can't quite do "whatever you want" with it anywhere in the world, at least until Alex dies, because in some countries authors have inalienable moral rights that cannot be waived by any agreement or license. For instance, if you go to France and distort or mutilate Alex's work in a way that harms his reputation or honour, he will be able to sue you for it, and no possible license will waive his right to do so; there is nothing whatsoever other than commit suicide that he can do to grant you the freedom to mutilate his work in a way that harms his honour while in France.
So the only way to make this truly "free" is for Alex to publish his work then take his own life? That seems a bit grim and too big of an ask. I'm sure this isn't what Breck wants.
Ok, so it seems the author of futurecoder.com has struck a nice balance. You can use it monetarily free. It's on github, so if you see something innovative, you can see how it's done. Even copy it to your computer. But can't do harm.
What intentions are left for Breck? Straight up plagiarize into a new website called futurecoders.io? Does he want to humiliate? Mutilate? I don't know what Breck's point is.
I'll also add that it has been copied and rehosted, with my help. There's a slightly customised French version here: https://futurecoder.forge.aeif.fr/
This version is meant for maximum user privacy. firebase has been disabled completely so you can't sign up or login and nothing is stored online. There's also no google analytics.
(Also as I understand it, it can be hard or impossible to contribute works to the public domain before automatic copyright terms expire in some countries, and that is the justification for CC0.)
I think breck's point is that, since many jurisdictions in the world grant authors inalienable rights over their works that cannot be waived nor transferred by any means (e.g. some "moral rights" in France and maybe other European jurisdictions are unwaivable), no license ever makes a work "100% free".
Which is true, but not spelt out clearly by breck, and it's kind of annoying for it to be phrased by breck in a way that leaves unclear whether it's merely a semantic nitpick or an actual suggestion that the author should've done something more to waive rights over the work. (I don't think it's the latter; I'm unaware of anything more the OP could do to "fix" this "problem" other than kill himself, and I'm not certain if even that would be sufficient in all jurisdictions.)
