Deoxyribonucleic A.C.I.D.
Kamehamehaaaaa!!
Anyone with half a brain running a wrestling promotion would push someone like Roman Reigns to the moon and back. Historically, the big tough looking guys have always been the draw and garnered the most interest. Me for example, I look much more forward to matches such as Brock Lesnar vs Samoa Joe/Strowman than I would say Hideo Itami vs Daniel Bryan or something along those lines. There is just something about 2 behemoths clashing horns that makes wrestling awesome. I can't speak on behalf of the general audience but just look at who the top draws in the industry have been:
Hulk Hogan
Stone Cold
The Rock
John Cena
All physically imposing badass looking guys straight out of a comic book. Roman Reigns has the look and despite the IWC's consensus, can put on some hard hitting matches. He's the guy you want on the late shows and being interviewed on the red carpet representing your company. Would people who don't watch WWE be more impressed with someone who looks like Roman Reigns or one of the cruiserweight/smaller guys? In ring ability, despite Reigns having some of the best matches over the last few years out of anyone, doesn't define you as a professional wrestler. If you think that's all that matters you have no idea how professional wrestling works.
So Reigns is being pushed just because he happened to be into that category of wrestlers. All WWE had to do was to wait. They didn't. Now it's over.
Also, you get the same feeling from watching AJ Styles come face to face with Finn Balor, as you do when you watch Strowman come face to face with Big Show, or Daniel Bryan come face to face with Andre.
SIZE DOESN'T MATTER IN 2017!
What matters is being entertained and connecting with the audience and delivering the most possible believable match. For example, Brock Lesnar. CM Punk. Daniel Bryan. Those guys became popular without being forced to us, because of the above reasons.
In-ring storytelling and suspension of disbelief.
Watching Roman Reigns take 4 AAs, 56 F5s and deliver 145 Superman punches doesn't do that. Watching the Cruiserweights jump around like they're a circus doesn't do that. Watching Dean Ambrose wrestling like he's having a seizure doesn't do that.
I remember watching CM Punk wrestle The Big Show once. And it was good. Why? Because Punk sold me the fact that he can take down Show, despite the size difference by using different methods.
Plus, we're just going to forget how hard Cena schooled Reigns one month ago?