Maybe he was the most successful manager of all time in terms of games to trophies ratios but when he came to us, POOF, just immediately became mediocre.
Or maybe some people are being overly critical because they don't like how respected he is and really want to believe that he's the Emperor with No Clothes because it reinforces their worldview that anybody who is successful is ultimately either corrupt or fluking it, because fuck knows they can't blame themselves for their own inadequacies and lack of ability to realise their ambitions and it must be the world that is wrong.
I'm pretty sure it's one of those but have yet to figure out which one.
I'm going to be the minority here and say that was fucking spot on Damo!