So you added this part to your comment after I started writing my response. A few thoughts:
In both places he's played he was competing for time against an older, more established goaltender who was also very good at the time (Holtby in Washington, Varlamov in Colorado).
One of the realities of being a "pretty good" goaltender is that I think your career arc often depends a lot on opportunity. If you're the only goaltender worth a crap on your team, you'll play a lot and probably be pretty well regarded. If you're always alongside a Holtby or a Francouz you might not play as much and will probably be consistently underrated.
Either way I'm more interested in his actual on-ice performance than how much his coaches used him. So that .920 matters a lot more to me than the other stuff.
But that's one way of looking at it. I'm certainly not claiming my way is the only way.
- Sven22
I know you're a big stats guy so I added it. I'm not a big stats guy but I've never felt that makes my informed opinion any less than. And I don't mind fans using stats to illustrate a point.
I always believe the cream rises to the top. The best players thrive on the opportunities they're given. Hasek backs up Belfour in Chicago but doesn't get to play. He gets traded to Buffalo and seizes said opportunity to become arguably the best goalie of all time.
A young Patrick Roy grabs the opportunity as a rookie goalie and leads the Habs to a Cup win in 1986. Billy Ranford takes over the net in Edmonton and wins a Cup in 1990.
Opportunity is a fine line. I bet that there were hundreds of players yelling at their tv screens during the Red Wings Cup runs saying they could also win 4 Cups like Maltby, Draper and McCarty did. But they were on lesser teams and never got that opportunity.