Good points from Luna. I’d add, cults (and I’ll thrown in religions like Evangelical Christianity in there) are anti-communist because they need people in society to be broken, desperate, and have little to no forms of social support. These cults/religions prey on people in a society that leaves them alienated from their fellow humans. The promise of socialism is that at a minimum, peoples needs are met - physical, social, and emotional.

IMO the overwhelming majority of adults who join cults or reactionary religions usually have some serious needs that are unmet. Communism threatens to cut off the cults’ supply of social reproduction.