I'm not sure how being polyamorous, having kinks and not hiding them makes someone part of a cult, even if I generally don't agree with Yud's entire thesis.
Separately, that other article also mentions harmful psychological practices like "debugging" and sleep deprivation.
Note that I make no claims of my own - for all I know both articles could be complete fabrications. I'm merely listing what these articles claim. I personally know none of these people, and live halfway around the world from them.
Common signifiers of cults include:
1. Apocalyptic world view.
2. Charismatic and/or exploitative leader.
3. Insularity.
4. Esoteric jargon.
5. Lack of transparency or accountability (often about finances or governance).
6. Communal living arrangements.
7. Sexual mores outside social norms, especially around the leader.
8. Schismatic offshoots.
9. Outsized appeal and/or outreach to the socially vulnerable.
Rationalism checks most of these boxes.