are you utterly thick? we're not going to change formation and the way we play when he comes on in games. He'd still be required to play a high line. Also what happens when one of our starters is injured? you think Ange will just abandon the way we play because Bonucci has to start.
God give me strength.
God give you the ability to read.
I'm not saying he should be a starter, and yes - sometimes teams change formations later on in games. His experience would help develop our young and sometimes rash players. Hope this helps.