I watched the whole thing. Starting at the 8:40 mark, Rob discusses the “vent screens” and their need for cooling the batteries that will run the “on-board fans, audio/music, and lighting”. He uses the word “definitely” multiple times.
Perhaps I’ve missed it, but this is the first I recall hearing about on-board fans, and for sure he is the the first I've heard say that there will “definitely” be audio, music, announcements, and lighting in the actual gondolas.
His comments about “maybe” adding AC in the future is sure to trigger another 600 pages of debate.