Pope Paul VI was the last pope to wear a tiara for his coronation. He decreed that thereafter no other pope would wear one. As a result, popes now wear the pallium (stole) as their sign of office. For coronations, popes now wear a mitre (albeit generously decorated).
The seal of the confessional would prohibit Dom Tammaso from discussing the confession the Pope just made outside of the confessional even in such general terms.