Why didn’t people (apparently?) understand the metaethics sequence?

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:

  1. I read Three Worlds Collide before doing my systematic read-through of the sequences.

  2. I have a background in academic philosophy, so I had a similar thought to Richard Chapell’s linking of Eliezer’s metaethics to rigid designators independently of Richard.

Reading the comments on the metaethics sequence, though, hasn’t enlightened me about what exactly people had a problem with, aside from a lot of arguing about definitions over whether Eliezer counts as a relativist.
What’s going on here? I ask mainly because I’m thinking of trying to write a post (or sequence?) explaining the metaethics sequence, and I’m wondering what points I should address, what issues I should look out for, etc.