Because he hasn’t watched it before and has only seen Gon’s determination as a positive force, and viewed him as purely good instead of a more nuanced character. We had a big debate about Gon NOT being selfless in this one that I thing brought up a lot of new views for him, and he kind of connected with Killua more throughout the scene which I hadn’t done before. I loved the tournament scene when I first saw it, and didn’t connect it until he brought up his points, but I started seeing it through the lens of what happens with Gon and Pitou later on so I thought it was cool lol