The fact that you consider 1988 to be "fairly recently" shows how badly US copyright laws and lobbying efforts have skewed people's perceptions. In 1988, there was no Facebook, Youtube, Google, Amazon, or web, cellphones were virtually unheard of, many of the people on this forum were unborn, the Berlin wall was standing and Michael Jackson was at the top of the world. It was a long, long time ago.
The justification for intellectual "property" is to encourage creators to work that will eventually belong to the public. I cannot believe that an author's decision to write a book at that time was influenced by whether or not could continue extracting profits in today's world.
The original copyright term of 14 years might have been defensible for books in that time, but extensions are very, very hard to justify in terms of the benefits to society.
And I think you may be closer to the mark with 14 years than I was with 25, though some franchises continue to be active longer than 14 years. The Simpsons for instance are still producing new episodes after roughly 23 years.
Either way, 1988 is extremely recent in comparison with the way the current copyright laws are written and many other books that are still under copyright after multiple decades. I may disagree with the law as it is now, but until we manage to get it changed, it is the law.
The justification for intellectual "property" is to encourage creators to work that will eventually belong to the public. I cannot believe that an author's decision to write a book at that time was influenced by whether or not could continue extracting profits in today's world.
The original copyright term of 14 years might have been defensible for books in that time, but extensions are very, very hard to justify in terms of the benefits to society.