It’s whatever the “news of the day” is. It’s what everyone is talking about.
It might be an event, like the coronation of the new King of England, or the Women’s football World Cup Final, or the cinematic release of two movies (“Barbenheimer”).
Usually, hype will feature in the news, we call this “mainstream hype”. Sometimes, for whatever reason, hype will not be covered by major news outlets. We call this “underground hype”.
Regardless of the type of hype, Mario goes through a pipe, and we sell t-shirts.