The thing about Zacha is that he's always been this capable. I'm not sure what the issue was in NJ, but there was an issue.
In 2015-16 He played on a stacked Sarnia team with Jakob Chychrun, Travis Konecny, Jordan Kyrou among others. Zacha was dominant on the PP and a threat to score on the PK every time. The problem then, as it is now: He had/has a great shot but doesn't play selfish enough. He doesn't use it as often as he should.
I think the coaching staff will eventually get it out of him. I think he's got more to give.