Cults. Seek to isolate the members from the outside world, including family & friends.
Use aberrant methods to control the group, peer pressure, sleep deprivation, food allocation, public humiliation. Generally one personality as a leader but not always exclusively. Requiring strict adherence to rigid rules. Odd requirements such as conforming appearance, constant companions, sexual favors.

It used to be a cult, but now it's a religion.

The difference? In a cult there is a person at the top who knows it's all a scam. In a religion, that person is dead.

OHHHHHH, yes! And it destroyed a large group of people who sincerely wanted to help others and do ''good works." Jim Jones was a horrible person who, had he somehow lived, should have been charged with 900 counts of murder!

The peoples temple, Heavens gate, Branch dividians, Claire Profit outfit in Idaho, any time you are demanded to follow blindly and never question its a cult so that includes all religions

Kind of the wrong question since the definition of "cult" is hardly agreed-upon. The snarky definition is "a religion that is too new and/or too small to have been normalized by society".

I imagine they're going with a definition based on being extremely controlling of member's behavior, but I would characterize much of fundamentalism as guilty of that, and yet they are mostly considered "evangelicals", not a cult.

Or they might be going with the notion of not subscribing to one of the recognized historic creedal statements of Christianity, such as the Nicene Creed, but Mormons and JWs don't do that and yet want to be called Christians, and are considered part of Christianity BY many Christians. Only fundamentalists would call them cults anymore. They believe Jesus is god and the Bible is inspired (if not, in the case of Mormons, exclusively so) and so they can argue they are Christians.

Even the definition of "Christian" has many facets. There's cultural Christianity, Catholicism, Protestantism, certain sects like the Holiness movement that consider the rest of Christianity watered-down at best and heretical at worst.

Anyway ... this video is a good analysis of the People's Temple's history and beliefs, cultic or otherwise it was nuts.