I don't see Columbus selling off soon, and probably not likely since they should be good, it will be interesting to watch simply because of how all in they will have to feel. As bad as Tavares leaving the Islanders was, they were a weak team with him, that can now focus on a full rebuild and had a good number of draft picks and budding superstar.
Columbus would fall directly from contender to mess if Panarin and Bobrovsky just walk. It's not that they will be worse then the islanders, but I would argue with the way the draft system works, it hurts more to drop from contention to mediocrity than it does to fall from mediocrity to the basement.
So a bad stretch of games in the middle of the season could put a lot of pressure on Columbus if teams like Carolina and New Jersey keep playing very well.