I don't think his finishing is better at all this year. Higuain has taken 153 shots and scored 26 for Napoli. Morata has taken 75 shots and scored 12 for Juventus. That's right around 6 shots per goal for each of them. Almost identical. As is their goal per minute ratio, while Morata's assist per minute ratio is way higher.
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The huge majority of goals in that video are finishes inside the box. Not running at defenders from midfield area. Most of them are either simple finishes of passes and crosses in the box, through balls received that put him through on goal, or Higuain making a move or two at the edge of the box and firing.
Very few of them are him running at defenders, dribbling into space, and then shooting.