Yea, but Reagan and Gorbachev were heads of state. Sure, the Pope is TECHNICALLY a head of state, but is he really negotiating tariff prices or talking about the Vatican's oil exports? No, he's coming as a representative of the church, not President of the world's smallest city-state.
I just think "the pope's visit" is one of those evergreen news stories that don't mean anything except that people get excited whenever it happens. And most of those people are excited because they remember the LAST media circus where there was tons of news coverage. It's a self-fulfilling news story.