I edited the post after you replied, I'll put the main crux of it again:
It also doesn't help that when a guy goes onto the main roster, they're put on the Zazz Train to Zazzville, and because they try way too hard with it, they end up taking away what was great about the character.
Take Bray Wyatt, the reason why he was so "scary" was because you could run into a guy like Bray Wyatt. A delusional religious zealot, who believes himself to hold god-like powers, and he's convinced these two huge, crazy motherfuckers that he does, and are willing to do his bidding for him. You see that shit in the news all the time. Then he gets to the main roster, and they make him "spooky", he's not "spooky", he's a fucking psychopath with a god complex, they made him less scary, by making him "Scary".
They did the same with Bayley. In NXT, she was a positive, nice girl role model, who still knew how to get the job done, after she gained confidence after being a superfan who got nervous on the WWE stage. Then, on the main roster, she became a 13-year-girl.