I'm not saying Bennett doesn't have any offensive ability. It's taken him 6 years to become a top 6 forward capable of contributing regularly, and even then, in the regular season he's scored at a .48/40 point pace. That jumps to a .71/58 point pace. That jump is impressive when the floor to jump from is so low.
As for the bolded, this isn't Draisatly or MacKinnon, who literally raise their game in the playoffs at an absurd rate.
Greig is 2 full seasons into his career. He can absolutely hit Bennett's current levels of production given how much development he has left and how he doesn't have as much PP time.