1- There are inevitable conflicts between practically any two creatures on this planet as to what preferences they would have as to the world. If you narrow these down to the area classified by humans as "moral" the picture can be greatly simplified, but there will still be a large amount of difference.
Sure, as I said at the end, the "universality" of the whole thing is an open problem.
I dispute that moral sentences ARE about the attitudes of people. Most people throughout history have had a concept of "Right" and "Wrong" as being objective. This naive conception is philosophically indefensible, but the best descriptor of what people throughout history, and even nowadays, have believed. It is hard to defend the idea that a person thinks they are referring to X and are in fact referring to Y when X and Y are drastically different things and the person is not thinking of Y on any level of their brain- the likely case for, say, a typical Stone Age man arguing a moral point.
That's fine. But in that case, all moral sentences are false (or nonsense, depending on how you feel about references to non-entities). I agree that there is a sense in which that is true which you outlined here. In this case we can start from scratch and just make the entire enterprise about figuring out what we we really truly want to do with the world-- and then do that. Personally I find that interpretation of moral language a bit uncharitable. And it turns out people are pretty stuck on the whole morality idea and don't like it when you tell them their moral beliefs are false.
Subjectivism seems both more charitable and friendlier-- but ultimately these are two different ways of saying the same thing. The debates between varieties of anti-realism seem entirely semantic to me.
1- Alright. Misunderstood.
2- There are some rare exceptions- some people define morality differently and can thus be said to mean different things. Almost all moral sentences, if every claim to something be right or wrong throughout history count as moral sentences, are false/nonsense, however.
The principle of charity, however, does not apply here- the evidence clearly shows that human beings throughout history have truely believed that some things are morally wrong and some morally right on a level more than preferences, even if this is not in fact true.
There seems to be a widespread impression that the metaethics sequence was not very successful as an explanation of Eliezer Yudkowsky's views. It even says so on the wiki. And frankly, I'm puzzled by this... hence the "apparently" in this post's title. When I read the metaethics sequence, it seemed to make perfect sense to me. I can think of a couple things that may have made me different from the average OB/LW reader in this regard: