In recent news, a pastor was criticized for calling Mormonism a cult.
Cult in typical American English usage is definition number 5 in MW:
great devotion to a person, idea, object, movement or work (as a film or book)
For example, the film Blade Runner is considered a cult classic. In this case, there are fans of the film who really like the film a lot and will buy the "director's cut" of the film and have collector's items associated with the movie and know many details about the film and the making of the film.
Certain musical bands garner a cult following.
Some libertarians would be described as very devoted to the writings of Ayn Rand and that devotion seems cultic to non-devotees.
In these contexts, the term cult is somewhat descriptive and depending on tone of voice may or may not be a disparaging.
Cult in a religious context tends to be disparaging as it usually describes a religiou…