sechel, not everyone views learning chassidus as a positive. Also, quoting the Shulchan Aruch haRav to defend Chabad is like painting a target around an arrow. I don’t know of anyone other than Chabadniks that actually uses it to pasken halachos. It was written by a Chabad rebbe, so Chabadniks follow it. Almost nobody else does.
n0mesorah, no, I didn’t misunderstand. The role of the tzaddik is a key element in the original teachings of the Besht.
As for tefillin on Chol Hamoed, it’s not just the Zohar. The Gra also held that one shouldn’t wear tefillin.