In this clip Vivek is discussing bitcoin with an old friend, not a random interviewer. His casual demeanor is appropriate for the situation. (Normally Vivek is fully suited up.)
What Vivek is SAYING is orthodox techie talk, not unusual. What he’s DOING is more interesting. He’s drawing diagrams and using them to illustrate his points.
No politician has ever been seen drawing. Occasionally we’ll see them writing notes in a formal debate situation, which seems fake. Even artists don’t draw in public.
Incidentally, this is a good example of The exception proves the rule. Most social taboos are so absolute and unspoken that we don’t even know they exist until we see the SALIENT exception.
Polistra's Mill 