WWE Hall of Famer Gerald Brisco recently said that nowadays fans are very smart and they are not like they used to be during the previous days.
Fans have changed a lot with times. Previously, fans used to cheer or boo wrestlers according to their gimmicks. Which means they cheered for the wrestler whom promotions wanted them to cheer for and they booed those whom the promotions wanted them to boo.

Gerald Brisco Says Fans Are Smarter Than Before These Days
Even the wrestlers like Stone Cold Steve Austin and The Rock have been booed by fans back in the day just because they were heels. Nowadays it is not possible anymore. Fans do not care about the wrestlers’ gimmick anymore.
For example, John Cena has been booed thoroughly for a long period of time inspite of being a babyface. Same happened with Roman Reigns too. On the other hand, wrestlers like AJ Styles and Kevin Owens have been cheered even after being a heel.
WWE Hall of Famer recently spoke to Wrestling Inc. Daily where he looked back at his time and the fans from back then and compared with fans nowadays. He said fans are really smart nowadays;

“Crowds back then didn’t know nearly as much as today’s crowds. Today’s crowds are the most educated crowds. And I’m talking about not just your casual TV viewer, I’m talking about somebody who buys a ticket, goes to the arena, sits down, and watches the matches at a live event.
“Those people are so much more educated now and have so much more knowledge. Not only about the people in the ring wrestling now, but most of them have done research and know about guys like me and know about guys like my brother. They know a little about it.”
He also said that local wrestling territories were a threat to WWE back then;

“In places that were established like Florida and the Carolinas it really didn’t hurt that much because they had such great talent and such a great promotion going on. But your borderlines your Kansas Cities, your Tennessee, some of the western states that didn’t have solid promotions [were more at risk].
“The territories that were solid in the beginning, they were okay. And they had the NWA Alliance, so they could send some of their talent out and be on cable TV out in Atlanta, and get their guys over like national stars. So as long as it was being a cooperative type of deal, it wasn’t hurting anybody.
“But the established territories, for the first few years, cable didn’t bother them. When Vince and everybody started wanting to go nationally, that was when [territories] started [being at-risk]. There was probably a ten-year timeframe from when cable hit till the demise [of territories] came.”