I think we are largely agreed as to facts and disagree only on whether it's better to call Eliezer's theory, which is intermediate between many realist theories and many non-realist theories, "realist" or "non-realist".

I'm not sure, though, that someone who says that "this is good" = "I want to do this" is really a typical non-realist. My notion of a typical non-realist -- typical, I mean, among people who've actually thought seriously about this stuff -- is somewhat nearer to Eliezer's position than that.

Anyway, the reason why I class Eliezer's position as non-realist is that the distinction between Eliezer's position and that of many (other?) non-realists is purely terminological -- he agrees that there are all these various value systems, and that if ours seems special to us that's because it's ours rather than because of some agent-independent feature of the universe that picks ours out in preference to others, but he wants to use words like "good" to refer to one particular value system -- whereas the distinction between his position and that of most (other?) realists goes beyond terminology: they say that the value system they regard as real is actually built into the fabric of reality in some way that goes beyond the mere fact that it's our (or their) value system.

You may weight these differences differently.