One of my favourite examples of games that are hard to train an AI on is The Legend of Zelda for NES. Many other games of the NES era have (at least in the short term) a goal function which almost perfectly corresponds to some simple memory value such as score or x-position.
Not Zelda. That game is highly nonlinear and its measurable goals (triforce pieces) are long-term objectives that take a lot of gameplay to obtain. As far as I’m aware, no AI has been able to make even modest progress without any prior knowledge of the game itself.
Yet many humans can successfully play and complete the first dungeon without any outside help. While completing the full game is a challenge that takes dedication, many people achieved it long before having access to the internet and its spoiler resources.
So why is this? Why are humans so much better at Zelda than AIs? I believe that transfer knowledge has a lot to do with it. For starters, Link is approximately human (technically Hylian, but they are considered a race of humans, not a separate species) which means his method of sensing and interacting with his world will be instantly familiar to humans. He’s not at all like an earthworm or an insect in that regard.
Secondly, many of the objects Link interacts with are familiar to most modern humans today: swords, shields, keys, arrows, money, bombs, boomerangs, a ladder, a raft, a letter, a bottle of medicine, etc. Since these objects in-game have real world analogues, players will already understand their function without having to figure it out. Even the triforce itself functions similarly to a jigsaw puzzle, making it obvious what the player’s final objective should be. Furthermore, many players would be familiar with the tropes of heroic myths from many cultures which the Zelda plot closely adheres to (undertake a quest of personal growth, defeat the nemesis, rescue the princess).
All of this cultural knowledge is something we take for granted when we sit down to play Zelda for the first time. We’re able to transfer it to the game without any effort whatsoever, something I have yet to witness an AI achieve (train an AI on a general cultural corpus containing all of the background cultural information above and get it to transfer that knowledge into gameplay as effectively as an unspoiled Zelda beginner).
As for the Fourier transform, I don’t know. I do know that the Legend of Zelda has been successfully completed while playing entirely blindfolded. Of course, this wasn’t with Fourier transformed sound, though since the blindfolded run relies on sound cues I imagine a player could adjust to the Fourier transformed sound effects.