What a great Thread and a thoughtful opening Post Joey jojo !
I think the main two reasons are as you say, either Pride of Loyalty, plus a dash of the Mind Control working too.
The Mind Control works because first off , their minds are switched to " Protect" mode, so that any info. that comes their way that might be disturbing is dismissed as " Apostate lies", or they fend off thoughts by applying the "answer" fed to them by the Org, an answer easily proven to be wrong with minimum research, but they are taught not to do that either.
This self-inflicted ignorance, coupled with Pride and Loyalty, again personality traits that have been fostered by the Org, make it almost impossible for them to wake up. We see the same thing in operation in Political Cults as well.
I do not judge individuals harshly for this, I was one of those people for decades, never too proud to admit I was wrong, or the Org was, but I had a loyalty to the Org, being born in, and I was woefully ignorant, until the Internet helped and educated me.