We are talking about the mainstream US here.

Qiaochu_Yuan's argument was that debates over abortion are privileged questions (discussed disproportionately to the value of answering them).

I added that while this is true in regards to the specific nature of the questions, the underlying moral uncertainty that the questions represent (faced by the US population - lesswrong is pretty settled here) is one that is valuable to discuss for the population at large because it effects how they behave.

Givewell isn't worrying about moral uncertainty - they've already settled approximately on utilitarianism. Not so for the rest of the population.