I think it's a bit disingenuous to say group think makes us susceptible to manipulation. While I don't dispute that it's true and could be taken advantage of, the sense of belonging in a group has always been vital to physical survival over the course of human history. The VERY drastic evolution of our society has made it less required, but our minds haven't adapted to that yet, hence the things you see in the videos and books (aside: I'm working through the Kahneman book a second time).
In addition to group think being a survival instinct, it brings a sense of belonging and community, which are both vital for modern day psychological survival. If you take critical thinking to an extreme, you'll be pushed to the brink of paranoia. That isn't to say some of that isn't required (ie. people with a high level of distrust make for excellent investigators), but constant critical thinking is exhausting and drives away people when because with it comes a need to validate everything that is said personally. Yes there is a need for critical thinking, but it must be delicately balanced with trust and earnestness.
In addition to group think being a survival instinct, it brings a sense of belonging and community, which are both vital for modern day psychological survival. If you take critical thinking to an extreme, you'll be pushed to the brink of paranoia. That isn't to say some of that isn't required (ie. people with a high level of distrust make for excellent investigators), but constant critical thinking is exhausting and drives away people when because with it comes a need to validate everything that is said personally. Yes there is a need for critical thinking, but it must be delicately balanced with trust and earnestness.
