Oh, which reminds me of something that… I think it was S John Ross, said about setting design for RPGs. It was like… badly paraphrased, when you write a novel you make a question then answer it. When you write a setting you ask a question in a way that makes other people want to answer it, but doesn’t demand one answer.

Notably, one of his settings is one that gets brought up a lot in terms of good systemless settings. (Like, even in this thread.)