When were the weight classes defined, the 1850s? They don't reflect the larger bodies of the population.
1999
"In the past 45 years, the NCAA weight-class structure has remained fairly consistent, with two notable changes. In 1987, the NCAA changed what had been the unlimited weight class -- better known as heavyweight -- to impose a 275-pound upper limit, which was increased to 285 a decade later. In 1999, today's weight class structure was implemented, with competition at 125, 133, 141, 149, 157, 165, 177, 184, 197, and 285 pounds."
Good article from a few years ago :
https://intermatwrestle.com/articles/14234