These "property rights" you speak of are not natural rights. They were spun from whole cloth very recently. They have changed before, and they will change again.
What we're seeing here is the social pressure that will drive that change, for better or worse.
There is no such thing as "natural rights." Rights are utilitarian, or otherwise based on the morality of the society (relative, not absolute). Property is certainly spun from whole cloth. Animals after all do not have property rights, merely possession.
As for copyright being recent: there have been protections against copying creative works pretty much as long as it's been possible to copy creative works. In Britain, within 50 years or so of printing presses proliferating in the country, printing became the subject of government-granted monopolies (only those with a charter could print). Copyright was introduced in surprisingly recognizable form with the Statute of Anne in 1710.
"there have been protections against copying creative works pretty much as long as it's been possible to copy creative works"
Funny how in ancient times, there were cities that required that any books brought into the city be copied and stored in the library. It was because of the copying activities of monks and scholars that we have man ancient works, and nobody complained about them copying things.
Restrictions on copying entered the picture because of censorship. You talk about the pre-Statute of Anne copying restrictions as though they had anything to do with the creators of written works; those restrictions existed solely for the purpose of censoring authors. The side of effect of those approaches in English law was the creation of a large, powerful publishing monopoly, which is how the Statute of Anne was created in the first place (the lobbying effort was led by and almost entirely consisted of the businesses that had benefited from the previous system).
As for copyright being recent: there have been protections against copying creative works pretty much as long as it's been possible to copy creative works.
Point for discussion: if life has a purpose at all, then that purpose can be phrased as "Making copies."
If only people agreed on what natural rights were, we wouldn't have any disputes. I know people that think that if you leave a house sitting empty, they have a natural right to move in and begin living there. It'rs real easy to invoke natural rights when you end up as the beneficiary.
As for recently, since the creation of the cosntitution creators have been granted copyrights 'for limited times'; No matter how much you hate the fact that Disney is still claiming copyright on materials almost a century old, retransmission of TV happens over such a short timeframe that it surely falls within a reasonable definition of 'limited times.'
What we're seeing here is the social pressure that will drive that change, for better or worse.