Why you want to reduce value of creative work, but not a value of other assets? I think copyright should be as long as ownership of any other asset.
If I spend $20m on building a house or creating a computer game, why house can be inherited indefinitely and creative work is not? I would have a monopoly on this specific building and on this specific creative work, but anyone is free to build/create anything else.
If J. Rowling created Harry Potter universe, why her family can't own it indefinitely? We somehow accept this notion for other assets, but treat copyright differently.
p.s. creative work is more valuable as it has something that money can't buy (authenticity, taste, sincerity, etc)
>Why you want to reduce value of creative work, but not a value of other assets?
The framing isn't charitable. People want to weaken copyright because it is a government granted monopoly. There are negative economic effects (i.e., for everyone) to government granted monopolies. Other assets generally aren't government granted monopolies.
>If I spend $20m on building
Why don't the builders get infinite royalties on use of that house? Wouldn't that also be reasonable. At least as long as it stands. I don't think that would be unfair comparison.
Her family can own their copies of Harry Potter forever.
But copyright restricts others from building on top of previous works. Can her family forever sue anyone into poverty for naming a wizard “Harry”? Does that even make sense in 100 years from now when most people have never heard of Harry Potter anymore?
For your building analogy, it would be more like the builders created your building there, and now you own it. It has a red roof and blue shutters. And also the government passed a law that said nobody else can own a building ever again with a red roof and blue shutters, otherwise you, the owner of the idea of those colors, can take possession of every new building like that.
> why house can be inherited indefinitely and creative work is not
Because copying houses is inherently expensive, while copying creative works is inherently free. To make creative works act like houses you have to add artificial cost to copying, which is a tax the public has to pay for the entire duration of copyright.
If the public has to pay a tax they should get something out of it, and that something is the incentive for authors to create new works. But does copyright have to be for life + 70 in order to incentivize new works? Clearly not! It could be much shorter while still providing plenty of incentive.