Point 3 is rather silly in and of itself, I think, as it applies to any hobby that a person might pursue with sufficient interest and dedication, or even unhealthy dedication - “with religious dedication”. Take devoted collectors of <whatever>. Or people who are bookwormy enough to never let go of a book. Or people who train and work out alot, like fitness junkies. Or youngsters gaming away on their game consoles or computers. It even applies to people who have a job that they absolutely love, and that they spend all their waking hours thinking about. None of these can in any way or form qualify as a religion. Yes, you can say that some people approach them with religious like dedication, but that does not equate them with religion.
As for me, discussing pseudoscence like flat earth, creationism, alternative medicine, and conspiracy theories like holocaust denial is fun, and has required me to read up a lot of physics that I otherwise have forgotten or missed during my time at university. And to read up on biology, evolutionary theory, medicine, and history. Which is fun. I do it for the entertainment, for my own education, as well as to sharpen my own reasoning, debating, and writing skills. From the time I realised I was an atheist, I also took an interest in reading up on the bible, which I do now far more than back when I (thought I) belived in a god. Back then it was a chore. Now it is something I do with some interest, to read up on the ridiculousness, just like with flat earth(*). The amount of time I put into it varies, but I am nowhere near any religious level of dedication on it.
That said, point 3 (“a pursuit or interest followed with great devotion”) does not even include people who believe in a god, but don’t devote much time or energy into it, like those who only go to church at christmas, get wedded in church, baptise their kids, and just haven’t really thought more about it.
(*) In fact, I sometimes fantasize about how it could be a lot of fun to enroll in a bible study course arranged by one or the other christian sects around here, and to see how long it would take before they kicked me out for asking the wrong questions ![]()

