I have a theory that some of the reason the 80's were as open and crazy as they were, was because you really had to suck to miss the playoffs, or just be in the wrong division in any given year. Then to miss the playoffs for consecutive seasons, that's even worse. Today, it's easy to get lost in the wilderness. 3 years with no playoffs? Not that hard. A couple teams have gone damn near a decade.
The regular season has almost never meant more in NHL history than it does today, both in terms of money and the number of teams/playoff spots available, which plays a part in how conservative the game has gotten.