I'm hesitant to judge him. When you're side is playing badly, it's especially hard for forwards because they get few chances on the ball. To add, he's young and I'm not so sure he's surrounded by the best conditions to develop and reach his potential. His touch looked poor at times, unable to hold up play, not for lack of strength but just crappy touches which is not like him. He showed fleeting flashes of creativity that opened Napoli up in the first half as well though. Turns of pace and neat passes.
Strikers, more than any other position, are confidence players and with the lack of faith he's been given I'm not surprised he is low on confidence right now. He needs to play with a partner (Morata) regularly to make the right movement off the ball but he hasn't been given that chance. Despite this, he's got an assist and three goals to his name. You'd be a fool to write him off.