Kessler as a rookie is on par with 3rd year Gobert.

I don't think he will ever be able to guard the perimeter as well as Gobert, but he should become a better offensive player within 2-3 years. He's a better rim protector right now. I think he's the league's best rim protector already. So yeah, I see him as likely to become and remain an above-average starter for years to come.