How about he tells Tidus his opinion of the one sitting next to him right now?

"Nope. No way." Exposure to all the modern people on the train has made him fall back into speaking more the way they do than the formal way Inigo was taught to speak when he grew up whenever things get like this. And 'like this', I obviously mean 'dumb'. "Have you seen those things up close? It's awful! Can you even imagine how bad their breath must smell?"