How do you know?
It was introduced; people have mostly not made the argument that it was beneficial to society.
You could argue that the fact that it was introduced shows that it was beneficial to society, but that theory has problems with laws that are repealed. Prohibition was introduced for the same reason, that it was beneficial to society. And it was repealed because that was beneficial to society too. Is that... true?
I’m no great fan of the current IP regime, but the economics of building, maintaining and operating LLMs have the potential to completely gut human creativity and replace it with a mechanical ouroboros eating its own tale.