I think of 'Points of Light' as meaning something like the Wilderlands, with small areas of relative civilisation, and most of the world howling wilderness of ruins and fell beasts.
The typical D&D fantasy world has been more like Greyhawk/Oerth, with strong, civilised core kingdoms and adventure on the Borderlands between the Realm of Man and the wilderness/Realm of Chaos. Kalamar and Mystara follow this approach. They basically present a nicer version of 15th-16th century late-medieval and Renaissance Europe, with powerful states and large standing armies. Ironically, most of the middle ages were rather closer to the 'points of light' paradigm, with few powerful kingdoms and endemic warfare between competing nobles.
Forgotten Realms actually has fewer strong kingdoms and more wilderness on the map; FR's problem is the preponderance of uber-NPCs who seem capable of dealing with any serious problem, but it could be presented as a Points of Light setting.