Your copyrighted work just has to be an original expression, not derived from someone else's work. It doesn't have to contain original ideas.
Patents are for ideas. Patents do in fact expire far faster than copyrights in the USA. The main problem with patents is patent trolling in the area of software patents.
Because then the creative individual, in order to sustain themselves, will basically need an ultra rich patron who pays a lot of money for just the one copy or one performance. You know, basically how things worked before printing presses and recorded music.
Most copyrighted works don't make any money. Those that do go through a period where they sell a bunch of copies and after that it's just a trickle, if anything.
Why should you be able to charge every separate individual who comes to your concert? Same per seat price whether the place is filled to the back row or to the second row!
If you rent something, you're getting charged multiple times for exactly the same thing. You just paid for one month of staying in an apartment, now they want you to pay for a month again! The mere passage of time is churning out month after month. They are all the same, but you get charged! Same with power tools, cars and everything else rentable. Fifty people before you rented this hammer drill from Home Depot, but you still have to pay the same as they did.
Anyway, suppose that one should not be able to charge multiple times for the same thing. Then, fine, let the purveyor of an AI service also not be allowed to charge for their algorithmic rehashing of someone else's works.
I'm for getting rid of all forms of rent. But it has to be all: no cherry picking. Don't take away renting from one, while allowing another one to sell unlimited copies of a work. Or vice versa.
It would be a lot easier to defend copyright if it expired quicker.