Earlier quoted context omitted.
All copyright is way too long but authors go completely off-piste at anyone who suggests that it should be something more reasonable (I kinda like 21 years myself). Part of the issue is that the loudest voices are that 0.01% of authors whose work still has some commercial value decades after its creation.
There's an unexplored (to my knowledge) middleground where copyright expires more rapidly with regards to derivative works, but not the original. E.g. At x+10 anyone could make a new sequel to Zork, but the rights to the published Zork are retained for x+25 That feels fair.
Would the copyright holders of Zork get royalties in this scenario, like with cover versions of songs?
The other problem is that in this scenario people will just be slapping the names of things that were popular x+10 years ago on literally anything. People will just make the lowest effort loot box laden pay-to-win mobile games you can get onto the App Store, and advertise them as sequel or tie-in to that old popular game/book/movie.