If not for Chabad's intense identification with beards I don't think it would be as big a deal, the rest of us frum Jews don't see it as the same deoraisa (done properly of course).
In kiruv there is always the fear someone takes on too much too soon and isn't ready 4 it.
As he says he jumped in when he saw yiddishkeit was real and then was 2 afraid to take a step back. That's why he's expressing it so disagreeably (to some of us) now.
I don't think it's minhag and rabbi's that he's throwing out as much as the fear culture he was living with, kind of like a chassidish kid from willy who finds out that if he reads a secular book he's still jewish (as long as he finds out b4 he sleeps with a shikse)