I'll preface this by saying I by no means suffer from blind homerism and can accept most criticisms against my team if there's a valid argument, there's no way Kipper could be considered overrated and I'll argue that any day of the week.
As it's been pointed out, he masked how bad of a team the Flames were while he was there and we really should have been rebuilding 4-5 years earlier at least. He stole games for us that we had no business winning. The reason why he played 70+ games a season was because we depended on him that much because we were always just barely within reach of a playoff spot. I can't remember which season it was, but one year the coaching staff explicitly said at the start of the season they were going to minimize the games he played so that he'd be better rested for the playoffs and towards the final stretch of the regular season when we were chasing that last spot, he was in night in, night out again.
When Iggy left, I was bummed out but scorers come and go, but when Kipper retired, I really felt there was no way we'd get a goalie of his calibre again (and I still feel this way).