I ran into an issue whereby I created a hierarchy custom setting in my DX scratch org but when I used the SDFX CLI to pull down the metadata it was ignored.
I had used list custom settings before and that was fine. Of course, to use list custom settings you need to enable
Schema Settings > Manage List Custom Settings Type first.
As it turns out, after enabling that, I was able to update my original hierarchy setting and, voila, then able to pull it down with the CLI.
I could not find any documentation around this behavior but would like to know if anyone knows whether it is possible to create and pull hierarchy custom settings without enabling list types as well?