Janes in my view this is an area worthy of proper investigation re: cult techniques. Most of the current work looks at very personality driven groups, but I think the internet has created a new dynamic that definitely needs exploring and studying.
There are generally two types of cult - religious or therapeutic. I suspect this movement has stronger overtones of the therapeutic, especially given the heavy doses of psychobabble introspection often displayed by youtube personalities - it's my contention that various Youtubers, with the false intimacy and sense of community created by linked social media, function in a very similar way to more well understood Leaders in various sects.
No one joins a cult. They explore an interesting therapy or philosophy, one that seems to answer all their anxious questions, and it's not until they have been subject to intensive grooming that they may ever get a hint of what they gave got into, though those around them will often see it and feel helpless to stop it.
A lot of people have heard of love bombing - this is the kind of thing that young people will be coming across on various social media, and combined with parental alienation, it fosters a huge sense of identifying with the group.
The parental alienation will be accompanied by a nurtured paranoia and feeling of persecution. Again, every youthful insecurity amplified.
In terms of what we as parents can do to offset these techniques is, first and foremost, love unconditionally. Always an open door and listening ear. Be your child's strongest advocate.
But as has already been mentioned, don't fall for the drama. Part of the conditioning is the belief that their group is under very special persecution, and there is a constant adversarial undercurrent.
So, state your rules, but don't get drawn into slanging matches where you tell them they are brainwashed and their favourite instagrammer is a deluded liar, however much you may know it to be true. The more you reinforce that persecution narrative, the stronger it becomes inside them.
In fact, if at all possible, don't let your child lead you into long discussions about Trans at all - we've talked before on FWR about the language used to mark out who is in, and who is out, and a lot of the teachings of the Trans movement are not meant to clarify, but to confuse. You are much better off drawing you child's attention to the huge wide sphere of real life that will, hopefully, eventually make the obsessive internet-driven world of mastectomy scars, cutesy terms for experimental medical interventions and endless eggshell treading to make sure the most current terms are used for fear of cancellation, look like the pointless, empty shadow boxing it really is.
I hope some of this is helpful. It's the kind of thing I'd really like to write a book about, but I am pretty damned sure wouldn't get published atm.