He's not a forward, he'll be fine
ZAR's offence came, as best as I understand, from going to the dirty areas and winning the puck. The scouting reports told us to expect a bottom 6 grinder. He simply doesn't have the offensive skills to be an offence-first player at this level unless he becomes Hornqvist. He either goes to the dirty areas and plays physical or he goes to the AHL. That simple imo.
As for his ability... I do find it strange how a player worse than Kuhnhackl paced for over 30 points in his first season and a bit in the NHL while always having strong possession/team metrics. But I know that's not persuading anyone.
It's come up before that the Penguins' internal stats defines chances differently to the metrics provided by the NHL.