For a number of reasons, I don't like the duration of copyright depending on how long the author lives.
* It's age discrimination against older people.
* If the copyright ends up being owned by some corporation (or effectively owned: some corporation has exclusive rights), which is what usually happens for any valuable copyright, it seems weird that the duration should be based on the lifetime of the author.
* It creates problems later when it's not obvious who the author was or when the author died.
* It could easily be abused by authors adding their grandchildren as co-authors. (I'm a bit wary of mentioning this in case I give anyone ideas. It has happened already, but so far not very often, as far as I can tell.)
* It's age discrimination against older people.
* If the copyright ends up being owned by some corporation (or effectively owned: some corporation has exclusive rights), which is what usually happens for any valuable copyright, it seems weird that the duration should be based on the lifetime of the author.
* It creates problems later when it's not obvious who the author was or when the author died.
* It could easily be abused by authors adding their grandchildren as co-authors. (I'm a bit wary of mentioning this in case I give anyone ideas. It has happened already, but so far not very often, as far as I can tell.)