He might be a legend in your eyes, and rightfully so if you see what he's done at Arsenal, but he talks like his world would come to an end if he had to face them in a Barca shirt.
Like you said, Guardiola and the fans will be thrilled to hear this. He's just overdone it a bit. Simply saying you would celebrate in a somewhat more respectful way to the opposing fans is more than enough really.
Having preferred not to play against them is fine aswell, but that's the way it is, man up and do your job.