Future with unadvanced technology or no technology

It would just be regular fiction, maybe even medieval. It depends on how little technology has been developed. The LotR universe didn't make much technological progress for thousands of years.

>>31402
There's セカイ系, but that really describes the style (i.e. story taking a back-seat to worldbuilding) of Jinrui and SSY, rather than their setting.

i.e. Hoshi no Koe would be セカイ系, whereas Fallout would not.

>>31417
But medieval is specifically the Middle Ages.

>>31423
Thanks, but I'm looking for the name of a setting. Not the storytelling style.

Pretty common for post-apocalyptic anime, but not strictly the same (there's often some type of "lost technology").