Nah it wasn't that impeccable... Remember the home game against Bayern in 2016? It was in 2016, so it was between the 2 CL finals, in other words it was in the so called EuroMax era of brilliance, or so they said...
But the signs of his cluelessness was already displayed in that single game, where Bayern's CBs at that match could step into our own half freely passing the ball to their team mates... We couldn't pass the ball properly throughout the match and looking clueless...
Yes it was against guradiola's Bayern... But that should never excuse our own team cluelessness playing at our own home...
But also it wasn't just that game against a guradiola's team, in the next few seasons we would have similar matches in Europe where we looked clueless, or not even in Europe but also in Italy, there were matches like those, many fans lauded those kind of games as defensive master classes by the team and Allegri but in reality we were just clueless at going forward and forced to sit back hanging on the ropes...
That's where the overall trajectory of the club performances aligned with the kind of players that we got, so yeah it's not 100% Allegri's fault... Going from mvpp midfielders to Pjanic Khedira Mandzukic quads to what we have in the last few years... But the thing is, post Cardiff, Allegri's main weakness got exposed more and more to the point of where we at today.
Allegri's coaching style has no attacking curriculum in it.
Why do you think he got a melt down against journalists back then? Because somewhere deep down he himself knew that.
It got to the point where even random foreign tv commentators were laughing at his in matches tactics and coaching decisions...
All because somehow after all those years spent as a top coach, he's still unable to formulate any kind of proper attacking curriculum for his players... So naturally he prefers to defend leads no matter what players we have and against what team we face...
Last season coppa final was just another demonstration of that weakness and mentality.