I think that was an important point made at the end, thinking in terms of calling the correct terminology, in your own games, will help recall such subtleties when they arrise ..
7:44 why not the white knight fork one move earlier? Looks like he wins the exchange back straightaway. I don't get it. edit, oh that would be down a piece after black's bishop capturing again with check. Tough game, this chess thing.
5:05 fascinating that this is the first blood of the game. 13 moves deep into a rich middle game position and no material is yet off the board. Just little positional ideas.
I imagine this is because it is white who opts for the closed Sicilian by not playing Nf3 and d4. Black chose the Sicilian, yes, but white is the one who chooses whether it will be open or closed