The definition of a cult on Google is: “a system of religious veneration and devotion directed towards a particular figure or object. a relatively small group of people having religious beliefs or practices regarded by others as strange or as imposing excessive control over members.”

So then her group would be defined as a cult. Many people in practice treat her words as the authority and venerate her, and then famously attack others visciously for having other points of view.

You say she ‘may’ have plagiarised but she definitely has. She copied a book word for word. She plagiarised the book ‘The Presence Process’ by Michael Brown and he has said of this:

“Teal Swan is everything I hoped the writing of The Presence Process would protect people from” so that is sad.

https://www.celestialhealing.com/2015/11/fullmetal-plagiarist.html

There is a large cult group on Facebook for people who feel they came out of her cult, so obviously that is what they actually feel, rather than it being people that only want to attack.