MMA is a sport, that is why there are rules and regulations.
Other examples: Boxing, Muay Thai, and Kickboxing. Football, in it's early days didn't have many rules/regulations, but eventually needed it as people were getting way too fucked up. So to preserve the sport, just like with MMA, had to be done.

Size matters more nowadays because people are more skilled lol. Royce would get rag dolled by Lesnar, Couture, Fedor, Antonio Silva, Overeem etc etc. No contest, and any of those old schoolers would have been raped by the newer gen lol. (Actually some of the guys I listed did compete in bare knuckle fights, just not the original UFC).

Those fights back then were of less skill, significant actually. That is just fact, dudes were brawlers and tough guys back then. I pretty much described how fights would be if it was the old school rules today; deformed mother fuckers/facial reconstruction.

Be happy we still have elbows and knees allowed.