Speaking historically, we seem to have a rather large number of examples where societies were reorganized to take away individual decisionmaking (ostensibly for their own good) and they've all gone rather horribly.

BTW, that paper didn't have any numbers in it, and didn't really help answer the question "Is that really true that the majority of people don't know what will make them happy?" The biases it enumerated are I am sure common, but do they dominate the lives of the majority of people? I am doubtful, especially if the proposal is "we will take away all your troubles, just let us make all your major life decisions for you (including, almost always, the ability to revoke the deal)".