ChabadOrthodoxrabbi1995:
Yes, that is our mesorah, going all the way back to that gemara. And nobody called your deceased leader a heretic. But your theology does contain heresy.
Also, it’s not “bias” and it’s not “sinas chinam” and it’s not any sina at all, despite Chabad trying to deflect edited; in fact, as a card-carrying Chabad defender, you are obviously the one with the bias.
Most Jews appreciate Chabad’s services and therefore would have no reason to want to speak against Chabad’s theology. So, if anything, they would be biased in favor of Chabad.
But the Torah is truth, and you cannot corrupt it with your heretical theology of what was heretofore normative Christian theology, Rav Keller Zatza”l noted.
Anyone interested in the truth, including the quote from Rav Keller above, can find it at the Identifying Chabad Organizational Website. They also sell a sefer of the material so that you can learn it on Shabbos or Yom Tov or anytime.