A prudent pilot would have at least talked to the guy in question. A better one would have had him removed from the flight.
What is going to stop the tin foil set from claiming random people look suspicious? Can’t remove every “swarthy” looking Greek, Italian, Spaniard, Egyptian, Indian, etc. because someone doesn’t like their look.
I think if she felt the person was a real threat, she would have asked to be taken off the flight. Then her vocalized concern would have had more merit. IMHO.