The WWE was always the land of the giants and muscular wrestlers. Superhero characters and wrestlers larger than life itself were always at the top of the food chain in this company. Even though wrestling is not about that anymore, there still needs to be a guy at the top that is marketable and is the proper face of the company.
Just like with John Cena back in the day, the WWE believes that Roman Reigns is the right guy for the spot. While Cena probably was a good choice, Roman is not. Vince McMahon probably realizes that himself right now, but still, the fans these days are going to keep watching the product because of the brand and not because of the superstars.
Higher ups like the way Roman looks as he does have a look of a Superhero, a good-looking and tall man that the kids like. The show is PG, and the kids watching is a big part of what WWE wants to achieve. They need a character like Roman Reigns who always overcomes the odds and the adversity and wins in the end. They buy the merch because of that, they ask their parents to take them to the arena because of guys like Roman. That is just the way it is.
While there might be a lot of smart WWE fans that boo and dislike Roman, there are a lot of casuals like children, some women and even families who like his character. When a family sits down to watch something, even though they are not die hard wrestling fans but actually like it a bit, they are going to notice Roman and like what they see. A good guy that does everything right looks like he is larger than life and just seems dominating and imposing.
WWE never took the chance on Cena and they never will on Roman. The money can be made with his heel turn, but the company doesn’t want to risk anything. If these were the days of when they were competing with WCW, they would have turned him heel long time ago in order to switch things up and have people talking. Today, when they are by far the biggest and the best wrestling company in the world, they don’t need, nor they are willing to take any risks. People are still going to spend the money on the product, the same fans that keep booing him are going to keep watching. They like him at the top, and that is not going to change.