As a former wrestler I have thought about the question of why wrestling does not get the crowds that more popular sports do. After all more attention is given to sports with much less activity such as golf and baseball. Here are some reasons for its lack of attention:
1. It has promoted poorly. Dale Thomas was a rare exception in that in the early seventies the attendence at meets ranged from 1500 to over 5000.
2. Title IX has been killing college programs.
3. Many people confuse it with profession (faked) wrestling.
4. It is not very recreationally oriented.
The fact that mixed martial arts fighting has been so successful (and employing many wrestlers) shows that there is a demand for combative sports if they are promoted well. It seems to me that knowing about the athletes and making the sport dramatic is what is most important. The most popular sports also have a symbiotic relationship between the media and the sport. For an example, the Portland Trailblazers, needs the Oregonian and TV networks to publicize their games and help the public become familiar with the players. In return, the interest generate helps sell newspapers.