>>14134672WWE is absolutely not trying to get you to boo Rhea or Drew. They are heels only in the ceremonial sense, but they are not villains. They had Rhea feuding with Nia Jax, a legitimate heel, just last month and they presented her as a babyface in that feud. Same with Drew, they allow him to get his quips in and they showcase the fans cheering for him. They are presented as ordinary, reasonable people who fight fairly, do interviews, hug the kids and are only really "heels" because their personalities clash with the babyfaces.
They are tweeners in every sense of the word and WWE has a bunch of them at the moment. Of course you still have your hardcore heels, Logan, Dom, Theory, Santos, Reigns, Nia. There is always going to be someone cheering them but they are presented as cheaters, whiners, bullies, and generally terrible people. That's how you identify a heel in WWE. If they wanted people to boo Drew or Rhea, they would have them behave that way and would draw focus to the negative reactions they get like they do with Dom. They don't though, ergo they are not heels but tweeners.