You've almost got your wish. Every 20 years, Disney buys enough congresscritters to extend it another 20.
Do you think we should be paying the decendants of William Shakespere for the right to read his plays?
Here's what the Constitution has to say about it:
To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries;
How does that mesh with the idea of perpetual copyright?
It doesnt because it is completely bogus to conflate scientific inquiry, research and invention with the creation of art, music and literature.