Imagine if Harry Potter had very generous licensing, with Harry Potter-themed games all over Steam and itch.io. A Zachtronics game about casting Harry Potter spells An alchemy game with Hermione as the protagonist A yaoi visual novel with an off-site adult patch about Slytherin side-characters. A Harry Potter tower defense.
There are 1000-chapter webnovels like this already. There are billions of words of HP fanfics written by 12-year-old girls online. If not for lame Disney protections you would be flooded with this stuff everywhere else.
counterpoint: in the HP-fangames timeline you would have more effective filtering and tagging and would never see this stuff anyway. Steam couldn't avoid making this feature more effective because people would complain so much.