Clearly you are the person who did not think this one through because you obviously have no idea what groupthink is or how detrimental it is in practice. It has nothing to do with half believing one thing and the other half believing something else as you suggest, it is when the consensus of a group makes an irrational decision due to their lack of critical thought. In this case, literally tens of millions of Republicans have made an asinine decision that Trump is the "true President" based on a lie - so, yes, they have cornered the market on groupthink as well as stupidity.
For future reference, the dumbest posts on this forum can be found in the Qanon thread, or pretty much anything you have ever posted.