I remember on my purif I would chat with 2/3 people after sessions and discuss other matters in the world. There was a big obsession with government conspiracy, ruling elites, other religions and how they have been manipulated, drug industry, physciaritry etc which was all very interesting but I had the same question in my head all the time "why then would you not question the cos and it's past if you are so sceptical about everything else"
In GOING CLEAR, Wright introduced a trait of Scientologists which separates them from members of some other cults. He came upon it while pondering how Paul Haggis, a liberal, free-thinking, creative Hollywood type with a critical mind, could be a Scientologist.
When Haggis was in Scientology, he associated with a lot of other people in the industry who are not Scientologists, and was aware of what was going on in the world, not cut off. He called the trait Haggis had, being a "contrarian." These are skeptical people who question the status quo, and accepted norms.
You described it well, an example being the talk you heard in the sauna. Scientology attracts many skeptical people and some are like Haggis, enjoyed belonging to a group which is sometimes maligned for being so different and full of unusual concepts and what Scientologists think of as critical thinking about what you mentioned -- ruling elites, drug industry, psychiatry, etc.
So when Scientologists are asked why they don't know the history of their own group, or of Hubbard, they bristle at the suggestion. That isn't important, they think. They are the group which challenges all else, including the status quo. They have the bridge to freedom and all the answers. That can't be questioned! It's something you do, and then it's something you know.
What they don't see is that all the things you mentioned, questioning authority, the ruling elites, government, the evil psychs -- these are all things Hubbard did, so Scientologists, who think they are finding themselves, are being trained to think and be like Hubbard, complete with his cognitive dissonance, for example, his paranoia but feeling superior, including having superpowerz.
One time on an outing with some followers -- his wife told this story -- Hubbard tried to make some ripe apples fall from a tree using only the powerz of his mind. He failed. He couldn't make one apple fall from a tree. On another day, a very windy day in a city, he went out and used the power of his mind to knock some people's hats off. He was more successful at that.
If I were a Scientologist (I was never one), I think that if someone told me that Scientology was not about finding yourself as much as it was being like Hubbard, then I would be curious about who Hubbard was, and how Scientology worked in his life.
I would then reason with them that since Hubbard's achievements in this science of the mind seem to have taken place from 1950 on, his life is very well documented, unlike the founders of older religions. Rather than seeking a glorified biography of his life put out by Scientology, which has an interest in selling Hubbard books and courses, I'd recommend to them to read Miller's Barefaced Messiah, which is a more accurate biography.
Of course, this isn't going to reach someone who is deep in. But I think the question in your head, "Why then would you not question COS and its past if you are so skeptical about everything else?" is an excellent one to voice.
Of course, one problem is that Scientology does two things: It creates a glorified past for Hubbard and Scientology, which is sanitized of things which aren't glorious, like Hubbard's 22 year old son Quentin committing suicide, although he was an expert in the tech.
And the other problem is that it is forbidden to have doubt, and question things about Scientology, which trains you in loopy concepts like how to be certain about certainty. If there's one thing you can be absolutely certain of it's that Scientology works and it helps people. Any questioning of this constitutes having bad thoughts about Hubbard. Maybe a Scientologist could be asked, "Are they really good core concepts to have, if you really want to have an open mind, and learn to think critically? Shouldn't you be able to question everything, and look at both sides of things, including Scientology?"
Scientologists are afraid of having those thoughts, because they might lose their "wins" and gains, and end up in the dwindling spiral, and darkness for the next trillion years.
Well, unfortunately, I don't have any good suggestions.