Petra Moser explains that copyright protection for 19th century Italian operas led to more and better operas being written, but the evidence also suggests that intellectual property rights may do more harm than good if they are too broad or too long-term.
So the takeaway from this video is that intellectual property rights should be narrow and short-lived. Unfortunately when you look around you you see that there is increasing pressure, mainly from the US, for copyrights to be extended and made wider. Its not clear that such expansions are socially beneficial.
The video come from The CORE Project (http://core-econ.org).