I think the problem comes from our strikers having to sprint back towards our defense when we're being pressed. When the opposition is playing passively, it's easy for them to receive the ball, Mirko does it all the time.
But there are games in particular like Lazio in the Coppa, Bayern, Fiorentina, Inter, Celtic (at times) where the opposition is pressing and our backline + Pirlo is very deep creating a huge gap between them and the strikers. Then it's basically a race for the ball between our strikers and the CBs who are running through their backs. It's very uncomfortable for a striker to play like that IMO and so hard to get it right.
I think that's why Conte tinkered with that 3-5-1-1 at the end of the year.