Let's just make a list of a few basic wrestling skills that apply from 106-285
Neutral: double leg, high crotch, single leg, penetration on your shots, headlock
Top: half nelson, cradle, running the wings, arm bars, running the legs
Bottom: stand up, sit out, switch, granby
Now, put the average lightweight and the average heavyweight in a room together and have them drill these moves, and I guarantee you the lightweight outperforms the heavy in every single category except maybe the headlock and the half. Look at the quality of wrestling at Conseco when considering that basic list of skills (which every state-caliber wrestler should have) and it becomes obvious the heavyweights are actually much worse wrestlers than the lightweights. Can you even name me any "skills" heavyweights have that lightweights don't, besides pushing and shoving a guy to the ground and roling him over?
Because there are very few upperclassmen at these weights to start with. It makes sense that a weight that is mostly filled by underclassmen is dominated by underclassmen... and here is what I feel a lot of people fail to understand: JUST BECAUSE A KID IS A SENIOR DOES NOT MEAN HE IS A BETTER WRESTLER THAN A FRESHMAN. Wrestling skill is not based on age, and on average, the freshmen that fill the 106 lb weight class are better wrestlers than the seniors that fill 195, 220 and 285.
Like I said before, there are a few exceptions to the rule, and you just mentioned three of them. Obviously there are a few skilled wrestlers in those weight classes, but overall, the majority of their competition is weak. If we're talking about specific individuals, which is worse, a freshman, who's probably been wrestling since he could walk and has won numerous national titles, winning 106 last year, or a second year wrestler stalling his way to a title at heavyweight that same year?