Let me start off by saying I'm an active Mormon and I rated this a 7 so no, *all* Mormons aren't giving this the lowest rating.
I was raised in "the Church" and still attend, although I've never been die-hard religious so maybe that's why I can view this show at least somewhat objectively. I also lived in the Utah Valley for over a decade so I definitely got the full "Mormon experience" π
First off, let me start by saying that I've talked to a LOT of Mormons and at least in my experience, NO Mormon actually talks like they do in the show. I actually laughed out loud several times when they kept quoting scriptures or prophets or said "Heavenly Father" in almost every sentence. Lol. No. I get that this is a dramatization but oh my, it was so cheesy.
Also the portrayal of Brigham Young was a little bit of an eye roll. He was kind of a weird dude for sure and made some questionable decisions (as every human does btw) but making him out to be this scheming villain (again, for dramatic effect I'm sure) was a little over the top.
Overall the cinematography was great, the acting was phenomenal, and the story was shocking and engaging, although it was told a little too slowly. Bottom line, really good, interesting show with a few flaws.
Anyway, definitely worth a watch, and if you're Mormon and considering watching it, just relax, enjoy it for what it is, and maybe learn something. "Fundamentalism/FLDS" is obviously an extreme offshoot of mainstream Mormonism and most people know that, if they're not ignorant. Also, every single religion has done some pretty messed up stuff and justified it in the name of a higher being. I'm not saying it's okay because it isn't, but churches are run by humans and again, humans are flawed. Doesn't mean your whole life is a lie and God isn't real.
