What a diva! All joking aside, maybe he is bipolar. I remember on my first ship (I was in the US Navy) back in 2004 we had a new captain, he held a captain's call which meant the entire command had to attend.
There we are, assembled on the flight deck, he started talking, and the officer that was supposed to bring his notes did something wrong, the notes might have been out (not in the correct order), he proceeded to yell at him extremely loudly about how inept he was (behavior unbecoming of a Naval Officer) (his behavior not the poor sap he was yelling at) in front of the entire command.
I would have been more forgiving if this was an isolated incident, but it happened regularly to the point that most officers avoided him when possible.
He then see me or other enlisted and was the nicest person ever and acted as if you didn't literally see him spray spit on some poor officer's face just 2 seconds ago.
I then made it a point to observe the interactions (not a hard thing since he liked wondering around our work
center), and every time that he lost it, the "offending" party was really not at fault.
I can have this educated guess because I lived with my mother who suffered from bipolar disorder.
One minute everything was fine, the next I got a slap so hard my mouth was bleeding because I said something that sounded like something my dad would say (I was 11 at the time) of course I didn't understand what just happened. This happened for about 3 years where my mom would have these episodes and eventually got diagnosed and had to take medication for that for the rest of her life. Of course the medication helped because it treated the root cause (a chemical imbalance). But man those were some shitty times.
I have seen some other people going through that and the worse thing is that they don't realize they are doing it or if they do, the illness overrides their ability to control it. Hopefully your friend doesn't have that and is just that he really is a douche, but maybe worth checking out.
He might be otherwise a wonderful person.