then... it's about comparing any given point in that 2-D space with any other point.

Granted, preferring one particular 2D point to another may be read as running a scalar-valued comparison function on the 2D space (such a reading is not without problems, e.g. because real people's preferences may not be transitive, but let's ignore those details). However, from the existence of such a function it does not follow that "we should find the most efficient group and give it our entire charity budget" - this being the claim the universality of which I was contesting.