Not sure where it really comes from,

It's almost certainly from the golang struct https://github.com/kubernetes/api/blob/v0.32.0/apps/v1/types... or its more succinct generated.proto friend https://github.com/kubernetes/api/blob/v0.32.0/apps/v1/gener...

and, as you pointed out, the .dev one appears to just be alphabetical. In their defense, I would guess for humans that are looking for "paused" it's much easier to scan down to the "mnop" area and then look for "paused" than, lol, guess where the paused was introduced in the timeline of a golang struct