Nice video, particularly enjoyed the random dude swimming in the river in the background lol.

He spoke well on the way we psychologically close off, or narrow our worldview, in order to make assessments and decisions. He did not articulate very well what full closedness would be like if it's possible, or what dangers that would pose.

His discussion of politics is also pretty conventional. "Be open to new ideas" is a pretty basic tenet of good faith debate, but individuals are still left to go out into the world and close it off in various ways to determine what's true, what a political response should look like, and what policies to pursue. If you care about consequences, maximal openness is not necessarily superior.

As for how to find that balance between closedness and openness He doesn't tell us much other than finding the balance is important, without any practical way of knowing when you're "open enough".