Chiesa had 4 goals - 4 assists in 1204 minutes this year.
He had 15 goals - 11 assists in 3167 minutes last year.
His pace this year he would finish with 11 goals - 11 assists in 3167 minutes.
Hardly some staggering drop off
And that ignores that he also started slow under Pirlo and that pace picked up in the second half of season which it easily could have again this year when he would get to play with Vlahovic, as he got to play with Ronaldo last year.