"his sect is often referred to as a cult."  Often referred to by who? People who dislike that religion. Anyone can refer to religions they don’t like as cults. I could refer to the Catholic Church as being exclusivist, claims it's the only way to God, forces you to accept their ideology before you can have communion, most people are born into it, its leader the Pope is supposed to be the representative of God on Earth, has rabid anti-homosexual views, has had thousands of priests who are pedophiles, etc.