This episode is a breather. A palate cleanser. After all the emotional weight of the Silver Soul Arc, we need a reminder that Gintama is still a comedy at heart, Gintoki wearing Kyuubei's underwear on his head to avoid his friends is the most Gintama thing ever. The show is literally ending, and it's still making jokes. That's why we love it. It never stopped being Gintama, even at its most serious. The episode is a bridge to the finale, but it's also a love letter to the show's comedy roots. And honestly I wouldn't have it any other way.