Comment by yorwba

Humans may crave newness, but it only needs to be new to them and also still mostly recognizably familiar. So artists who spent too much time steeped in the output of prior artists ended up with Dadaist literature and abstract paintings, while the average person still enjoys conventional novels and paintings that look like something.

I'm not sure whether Harry Potter pioneered the "school + wizards" mashup, but the school has many aspects you would expect of a school (save for the wizards) and the wizards have many aspects familiar from previous fictional wizards (save for the school part.) The novelty comes from combining the concepts in more or less straightforward ways.

Even a writing AI that is only capable of taking an existing plot and adapting it for a different setting could produce enough reading material to last a lifetime by taking all existing novels in the public domain and putting each in a different random mashup for modern audiences. And I think many people wouldn't tire of this at all.