No each map is explained on that comm. You assigning it ‘imperial core’ and asking for an explanation is some JAQing off sealioning imo. Theses maps correlate how interests of countries align around various issues, and the ‘same map’ comes up a lot because of how these same countries often agree on things in contrast to the the rest of the world. It’s not some socio-political theory, it’s just the reality of how these countries align into blocs that correlate with maintaining the current US hegemonic status quo.
The two maps that really ‘explained’ this concept for me were the map of countries that ‘condemn China’s treatment of Uyghur Muslims’ contrasted with the map of ‘countries that recognize Palestine’. It shows how this bloc of countries want to demonize China while supporting the ongoing genocide of Palestine’s indigenous peoples. The principles they espouse are unmasked in the light of the truth of this comparison.