That's not a mistake I'm making. Assuming you're talking about bog-standard effective altruists---by (claiming to) value the suffering of people far away as the same as those nearby, they're discounting the people around them heavily compared to other people. Compare to anyone else who values their friends and family and community far more than those far away. Perhaps they're not discounting them to less-than-parity---just less than they are for most people.
But anyway this whole model follows from a basic set of beliefs about quantifying suffering and about what one's ethical responsibilities are, and it answers those in ways most people would find very bizarre by turning them into a math problem that assigns no special responsibility to the people around you. I think that is much more contentious and gross to most people than EA thinks it is. It can be hard to say exactly why in words, but that doesn't make it less true.
But anyway this whole model follows from a basic set of beliefs about quantifying suffering and about what one's ethical responsibilities are, and it answers those in ways most people would find very bizarre by turning them into a math problem that assigns no special responsibility to the people around you. I think that is much more contentious and gross to most people than EA thinks it is. It can be hard to say exactly why in words, but that doesn't make it less true.