Guys do some research about a guy who lost his job after not having beer with one of notorious captain in KAL.
Have you guys forgotten about all the accidents happened in KAL due to power distance and FO could not be assertive in cockpit to prevent that.
It's very natural for that guy to feel pressure if he has seen cases like that. Grow some balls? What's the point if you lose your job or make your life miserable in cockpit because he's scolding you every little mistakes.
I am sure he can be more assertive if they would allow him to do so without threating his job. Agreed?