I still dont buy it, its all about resource conversion.
There is more than one way to gain an early advantage. Early conquest is by far the most powerful when you have targets within a reasonable range, but it becomes a more uncertain gamble the further out you need to venture.
If early conquest is your preference when it takes 30 turns to get to your nearest neighbour, then that is your call. I'm just pointing out that on the Enormous+ maps one can pursue different strategies for long-term advantage, since the greater distances provide a security buffer for the earlier portion of the game.
Regardless of the differing effectiveness of starting strategies, I prefer not to be pigeon-holed into early conquest time and time again in order to be competitive. Larger maps provide a way out for me. Your mileage may very.