They shot this documentary in Iran and it's about Zoroastrians society. Well, it seems their priests' obvious senseless approach is pushing them to die out numerically.
When I look back at history I wonder how Arabs could conquer Persia while Sasanians were great empire for themselves and when I took a good look at how was society at that time, I noticed that Sasanians build an authoritarian Zoroastrian church-state empire and Zoroastrianism became oppressive and intolerable so Persians were discontent from Zoroastrianism and they couldn't take it anymore so Persians just didn't defend Persia under influence of Zoroastrianism in war.
By the end of the Sasanian period the authoritarian Zoroastrian church-state was immensely wealthy. This had positive and negative effects on the religion. The umbrella of the Persian church kept Zoroastrianism dominant in Persia. This meant Zoroastrianism stayed free from the influence of other religions becoming popular at the time (Judaism, Christianity, Buddhism etc). However, Zoroastrianism became more ritualised and oppressive under this church, demanding a large amount of time and money from ordinary Persians. BBC
For sure Islamic Arabs invasion and conquering Persia had devastating impact on Zoroastrians and Zoroastrianism but there is no one to blame but Zoroastrians themselves.
Absurd mentality has always been with religion and it will be and it is the main reason that religions come and go.
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