>What 1 item of advice re cults would give a young person?<

Sort of assumes that 'young persons' actually take advice - in my experience a rare event unless it follows a painful experience - by which time the advice is largely superfluous.

Bringing them up with the idea that they have an inalienable right to ask questions and receive answers and that anyone who seeks to take that right away is to be challenged and anyone who obfuscates is to be avoided,  probably sets them on the right route. Bloody painful if you're a parent though.

Nik