I believe rankings of any sort, on any level of competition, whether it be in football, basketball, wrestling, etc.......are subjective at best. Whether or not the media or the coaches produce them should not really be the issue. In football the media and coaches polls often differ. I would think a coach performing a wrestling ranking would have a very difficult time defending a poor or biased decision, especially with the critique and comments they would receive from the knowledgable wrestling folks in this forum.
That being said, rankings in general create dialogue, conversation, and debates and through those debates, ultimately enthusiasm and interest for that sport. As evidence just look at all the conversations and opinions that many have in this wrestling forum. Whether you agree with rankings or who produces them, really does not matter. Each of us has free will, if you do not like rankings or do not believe they are accurate, then you can choose to ignore them and if you do like the rankings, then you can choose to add commentary.
If Deiner was ranking football, he may put Gardner at the top of 5A, and that would be fine..........right up until Aquinas beat them on the field. I think it is important to realize that ultimately in all sports, results are decided on the field or in this case on the mat.