It would be like if I decided to just start publishing my own videos teaching every new trick that came out. Would be extremely unethical even if I added my own patter to it.
You misunderstood my reply and I was unclear as my reply is from a legal end of things and devoid of anything ethical/moral.
In direct contrast to point 1 of what
ikadiallah said, it appears they're asking only about what's legal. The word MOVE was explicitly used in which I replied accordingly. Both his question and my reply have absolutely nothing to do with ethics.
My reply includes the explanation on why anything in the public domain cannot be copyright. (I just didn't use the phrase "Public Domain")
On a side note, just because it's old, does not mean someone cannot claim ownership to it. Disney does this all the time with it's IP. They just have it set to expire so long, that no one alive now, would be alive when the copyright expires. However assuming the copyright law doesn't change, then an heir to Disney would absolutely be able to renew the copyright.
Sorry for any confusion.