You left out a few possibilities:
-The poster hadn't considered that argument
-The poster doesn't want to have kids
-The poster will have a finite number of descendants
-The poster's concern for the standard of living of his distant descendants diminish according to distance (for instance, he probably cares a great deal for his children and a similar amount for his grandchildren, but by the time you're talking great-great-grandchildren his empathy has diminished significantly)
-The poster's descendants will not want share his fondness for the Maldives
-The poster's descendants will move away from the Maldives for other reasons
I'm sure you can think of a half dozen other alternatives if you think for a minute.