I watched all the time then, I remember it pretty well. It was definitely the first fued on RAW, his feud with Y2J.
He got a MONSTER pop on his Raw draft and he was still pretty well liked. Then as a poster mentioned, he threw out some lame lines (Y2cheap) and stuck with them. He dropped a lot of the edgy stuff from his rapper character and replaced it with lame putdowns like that. Add in the fact that Jericho is a long time respected vet and it was a wrap. Classic case of a babyface losing his edge and abandoning the stuff that brought him to the dance. Similar to Diesel in 1995.
That's where the famous split chants started too. high pitched "let's go Cena!" followed by low pitched "let's go jericho!"