One wonders if Liu Bei might have been stirring things up a little
It is always possible that he turns, whether taking Yi would have inflated ambition (would not be the first that happened to) or perhaps he calculated at Sun Ce's death the odds were a little too dicey for him to claim power but Zhou Yu was loyal while he lived and that is all he can be judged on.
“You, are a rebellious son who abandoned his father. You are a cruel brigand who murdered his lord. How can Heaven and Earth put up with you for long? And unless you die soon, how can you face the sight of men?”