Cognitivist yes, moral realist, no. IIUC, it's EY's position ("morality is a computation"), so naturally it's the typical LessWrong position.

in the absence of justifiably-ignorable inside-view (non-communicable) evidence I myself hold

Universally valid statements must have universally-available evidence, no?

Interesting that alcohol can be just as effective as LSD or cannabis

Really nothing like LSD, which makes it impossible to write anything at all, at least for me.