Moody:
They had a few game developers with a massive output of games. The article said, that they simply changed a few words in the game manual (aka rules) of a game from a new game proposal and named one of their developers as the developer making it a new game. In one instance the real developer went to court and lost since the court ruled that the changed words made it a new game. Which proves that you need lots of money if you want to create a lawsuit. I think the lawsuit created a percentage of changes necessary.
You can't copyright, patent, or trademark a concept. If you were to rename all the properties in Monopoly, have a start square as opposed to the Go square, rename the jail as the clink, change all the cards, etc - you could legally publish it because while the rules sheet is copyrighted and there are various trademarks, they can't protect the method of play.
You could also rewrite the rules to D&D and call it Pathfinder. There's no way to protect the game system, just the specifics of the game. Role three 6 sided dice for stats. role a 20 sided die to determine success - that can't be protected.
Moody:
As for stories I think you need to change the character names. Lets say we got a novel where Flopsybunny burns Goodgulf at the stake. Goodgulf doing the witch water test with Flopsybunny would be a new story even though the result would be the same, but the use of the names would most likely be a copyright infringement
You have to do a bit more than just change the names. For example, I can't take an ecopy of Harry Potter and do a search and replace to make it Jerry Potter, but someone can (and did) write a story about Harry Pothead (a weed smoking wizard).
https://www.amazon.ca/Hairy-Pothead-Stoned-Sorcerer-Potter/dp/0615881238Lord of the Rings was rewritten as Bored of the Rings. Twilight FanFic was rewritten as 50 Shades of Grey, and anyone can write a version of a Star Trek story by shifting things around a bit.
I posted a super hero story here that included reinvented version of the Bat Man universe. Bat Man was called Owl Man, Wonder Woman was called The Amazon, etc. But the characters were more than merely renamed. Owl Man fights crime as a last resort, focusing on creating economic opportunities. The Amazon left her enclave to find her father (Aries), The Judge (Two Face) flips a custom coin to determine if someone needs a spanking, Cat Lady smells of cat pee - committing crimes so she can afford to rehome the 60 or 70 (I forget) cats that her great-aunt (who raised her) has.
Was that story inspired by DC comics? Sure. That's clear at a glance. Is it different enough not to challenge any trademarks or copyrights? Yes.
I posted another one that is obviously inspired by Shazam!, but again, the characters and setting is different.
Back to the original topic, I think that you would have to train an AI with hundreds, thousands, or tens of thousands spanking stories before it could write one worth reading. Alas, it doesn't seem as if anyone is training AIs that way.