Copyright should only have a term of life (with a minimum duration of 50 years in case the artist dies at 20-30) and that's all. Tell me one reason this shouldn't be the case. By then, the studios will have taken a profit (or been a commercial failure but that's not on us) and so will have the artist. After the artist dies, there's no reason to "support the artist" anymore and while there is the effect of post-mortem…
I agree with the gist of this, but I'm actually leaning towards a shorter copyright lifespan. Maybe 20? The reason being that I feel this better balances the need to benefit from your work (20 years is quite a while to be exclusively entitled to something) with the need for society to build on your work without threat of litigation. I feel 50 years benefits the former a bit too much at the expense of the latter. Just…
In point of fact, some kinds of work depend on the longer payback period. Children's books, for example, don't usually earn so much initially, but successful ones can be dependable earners for a long time.