Its all speculation as to why there were not many 4x champs through 1980, but I'll throw out a few theories! Shred them up as you see fit!
The limited number of divisions - e.g. one state meet through 1965 - two divisions through 1970 - etc - would have made it very tough to crown a 4x champ.
Another arguement against the "old timers" was there were fewer weight classes (9 classes, then 10, then 11, then 12, now 14) and they were pretty wide ranging often 10 lbs apart. This would have bunched some of the youngsters up with upper classman pretty quickly in the line-up.
Plus the average stature for an 18 year old was a bit different 30-70 years ago than now, so you might have seen more upper classman in the lower weights.
And, if hear say is correct (you know the old "we had to walk to school uphill both ways", etc), maybe it was tougher for freshman to make the team when rosters were 3 or 4 deep.
Steve Lampe was a 3x champ but could not make the team as a freshman. Some of the old NWKL lore indicates that often times the JV or third string guy might have been capable of earning a state medal, but could not crack the starting line-up because he had a state champ in front of him.
This was true in Hoxie at 133# in 1968 when the third string guy placed 2nd in the state after injuries, etc knocked the first two guys out of contention. And I'm sure you can hear the same type of story from any school in the state with a wrestling program.
Just a few theories. Let me know what you think. And feel free to hammer them as you see fit.