I think I have a different take on this. I think the Gophers will miss Murphy more than Coffey.
If you look at what Coffey provided - scoring, defense, ball-handling - the team will likely not have 1 player who provides all of that to the same level. But they don't need 1 player to fill Coffey's spot. They need 2 or 3 or 4 different players to each provide part of the puzzle. some points here, some ball-handling there, some defense over there, and you fill the gap. And - to be fair - Coffey had some up-and-down games during the season. We remember how well he played down the stretch - but we may not remember some of the other games during the season when he wasn't as efficient.
On the other hand, with Murphy, it was a near-guaranteed double-double every night. Oturu should be able to pick up some of the points and rebounds - but who picks up the rest? And who provides the presence Murphy gave the team, and the ability to hit big shots or get to the free-throw line when the team needed it?
I guess I just feel better about the prospects for replacing Coffey's production than I do about the prospects of replacing Murphy's production.
Would I have like to have Coffey back? Yes - no doubt. But, he's gone, and the team (and coaches) need to find a way to replace what he provided. I don't think the team is doomed to failure. This can still be a good season.