I still believe in Olli. Unlike Puljujarvi he hasn't been rushed. His D+1 year was a stall in his development, not that he regressed, but he just didn't move forward much.
Ever since he joined TPS I think his development has been on track. I think he would be in the NHL right now as an everyday player had he not been hurt. Imagine if he hadn't missed the summer too where he could be at.
If he doesn't feel right its better to deal with it now than have it linger. Hopefully he'll have the necessary time to get back onto the ice & in shape. (His conditioning seemed behind last training camp).
He's a talented player, he's got some size, smarts & he's a good puck mover. He also seems to elevate his game when the games matter. He can definitely still be a huge part of this next core. Hopefully he can get through this & put the bad luck in the past.