Yeah, I think that you're logic is a tad bit flawed.
Regarding Ryback, his push wasn't stopped because he wasn't getting over, it was stopped because of numerous accusations of other wrestlers that he was reckless and, allegedly, because he had a piss poor attitude backstage, treated fans like garbage at autograph sessions and trying to get him to promote WWE to local media, like every other top star in the company does, was like pulling teeth. If true, then he enjoyed the fame that came with being a top guy, but he didn't particularly care about the additional work it takes to stay a top guy.
As far as Bray Wyatt goes, I'd love to see some evidence that his popularity is on the decline. He's been off TV for a while and various reports indicate that something is in the works. If true, then maybe they're looking to start fresh with him upon his return. The biggest complaint I've read over the past several months regarding Bray Wyatt is that he, Harper & Rowan were fed to John Cena at Vince's insistence because of his paranoia people would stop "believing" in Cena. It's a complaint not lodged at Wyatt, but at Vince for frequently having Cena booked to look so strong that it's more of a detriment than anything else.
As for Roman Reigns, again, I've seen no signs that his popularity is on the decline. I agree with the notion that Reigns isn't ready to be given a top spot, if such reports of Reigns going up against Lesnar at WM XXXI are true. I think he has potential that hasn't been reached as of yet but, as for now, he's not nearly as strong, overall, as Ambrose or Rollins. I'm a fan of Reigns, as are a lot of others, and pointing out legit shortcomings he currently has doesn't change that.
As far as internet fans go, like everyone else, they're of varied opinions on just about anything and everything. That's life. However, I do think that the OP has pointed out something that can be genuinely applied to some fans. There are some fans who're so damn smarky that they'll turn on almost anybody who happens to make it to the main event picture in WWE. Whenever a wrestler is in the midst of a main event push, it seems like haters come out in droves whereas many of those same haters were bitching 6 months earlier that said wrestler wasn't being given a main event push. Sometimes the complaints are aimed at the wrestler, sometimes they're aimed at creative as the push isn't going exactly as they think it should in their own fantasy booking scenarios, sometimes it's a bit of both. We've seen it with Jack Swagger, Dolph Ziggler, CM Punk, Daniel Bryan and we're currently seeing it with Dean Ambrose and Seth Rollins. Those're the types of fans you can't please and any promoter would drive themselves crazy even trying to.