I am retarded but now I somewhat notice that Gege made Sukuna during his kitchen trip.
'Geniuses don't need his teachings, but those who do lack perseverance.' -Chapter 56 of A Regressor's Tale of Cultivation
Totally same opinion !I as a reader may be delusional.
But I am not that delusional.
Pocket dimension isn't ideal, but represents how it is used most in Xianxia. Domain is actually pretty good, but its more like "secluded paradise" or perhaps "isolated/hidden heaven".
洞天 is mostly used in phrases to represent a beautiful place, paradise, or blessed area, so it is quite flexible.

Reactions: ConansWitchBaby and NotaNuffian