Taken as an intentional insult though, it could be very historically literate. The south of Canaan seems to have peaked in prestige in the Neolithic and early bronze age. Afterwards, other than a handful of Canaanite sentinel cities, it was kind of an irrelevant rural backwater, and those cities fell off drastically in the iron age. The kingdom of Israel was a regional player with a lot of manpower, but compared to its neighbors of Aram-Damascus and the Sidonians, it didn't really amount to much in the grand scheme of things. Judah may as well have not even existed. When Israel was turned into Samaria, it was right back to being a footnote.

Painting the kingdoms as LARPing pastoralists who belonged to an older time is basically exactly what it would have looked like to the Tzorim, who had apparently bad relations with Israel from the mid-iron age onwards. Reinvoking that imagery is basically stoking a 2500 year old brotherly inferiority complex, if a highly esoteric one.