I think there is no point in hating on Biraghi who does his modest duty quite fine.
I can't actually name a single player who can play at this winger position the way Conte wants too at this moment.
I mean look closely to Atalanta , did you really see Gosens dribbling past our defender on 1vs1 occasions ? Did you see any special involvement from him that would make you to immediately sign him instead of Biraghi ? Did you see any action coming from Atalantas left side that you said , wow , this Gosens is gold?
ANd yet Gosens has 6 goals and 4 assits or smth like that ....
It's about tactics man. Atalantas wingers need to do shit , other then run and cross the ball (smth that Biraghi can actually do well) because the ball is held forward by their 2 attacking mids ( ilicic and gomez). They create space for the wingers to run to and distribute the ball around. Smth that we don't do because our attacking play is too direct and fast , it almost completely bypasses the midfield ball distribution and goes directly to the 1-2 comibinations of our strikers. If you move from defense position to attacking play that fast you can't expect Biraghi , Candreva or whoever else in their place to be ready in the attacking phase. There is a huge difference in a 3421 the way atalanta plays and the 352 we are playing now. The moment our build up play will be more fluent and slower , usually vs weaker sides which wait for us in defense , then yes we need a winger who can be an attacking threat.
Not saying that Biraghi is good or anything but just really stating that this position in this way of playing is quite hard. Other then Zanetti i don't know who else can run up and down the field like this and still be effective in both phases.