Qwert, it sounds like your rabbi is unfamiliar with communities that have strong rabbinic leadership. Talmidim of any gadol take their words as Torah misinai; go to any Yeshiva and you’ll see this, except for places like brisk where lots of guys go with no intention of being machniah themselves to rav avrohom Yehoshua, but this is an exception. In yeshivos we say that so and so got “farkoift” on such and such gadol.
Lubavitch has an entirely different look on their leader, which has been explained a ton on this and other threads. They think he’s omniscient, able to help them, fit to offer prayers to, doing mitzvos because he said to do them, etc….
I don’t think rav miller was “perfect,” as no one is. Rav miller himself writes that even Moshe rabbeinu was only infallible when speaking nevuah, but that on his own he could and did make mistakes, on his level, which of course we have no understanding of.
I wrote about why two prominent American gedolim said not to get involved in the anti-neo chabad controversy. Both of those gedolim changed their minds around the same time, as rav pam and rav miller were niftar in 2001. We find many gedolim misjudged people, going as far back as geichazi. Rav Moshe also trusted his son in law…. And if you’re an east sider, well, enough said, you know the stories probably better than i do.
Just as an aside, one of the big roshei yeshiva said that the twin towers fell after the protection of the “two towers” in new york were gone. That stayed with me for 2 decades.
Re, Thanksgiving; rav moshe doesn’t say it’s a mitzvah or that you should do it, just that it’s allowed. Many good jews did it years ago, but the yeshiva world completely abandoned the practice 25-odd years ago. It’s also dependent not so much on halacha issues but on historical facts. Rav Moshe didn’t speak English, and presumably relied on information from people. Rav miller was a college graduate. The latter said that historically the holiday was meant to thank the Christian deity based on research, so this isn’t a machlokes in halacha so much as in netzius. I’m not saying one isn’t allowed to follow rav moshe in this regard, just “food” for thought.
Re, Rabbi kook. Rac shlomo zalman had a lot bigger things to do than delve into the controversy. I doubt he ever even read the books which were controversial or heard about calling Rembrandt a “tzadik,” edited or the rest. Rav Shlomo zalman wasn’t a zionist. He just sat and learned.
Other talmidim, like rav hutner, publicly distanced themselves from him. but this is a tangential topic.
As for the question about why we would bother paskening on shomayim issues, this question was asked by rishonim. The answer is that whatever we pasken in beis din shel matah, is followed by beis din shel maalah. This is why we have machlokes in mishnah and gemara about chiyuvei krisus, misa bidei shomayim, etc…