I also don't much care about Reigns/Cena just because I like matches, especially title matches, where the outcome isn't super obvious. Not to say the match itself will be bad, because you know Cena will probably try his best to continue making Reigns look like a fucking badass, I would just rather WWE use championship opportunities to showcase their full-time stars, even in losses.
That being said there isn't a fucking universe where you could take those four specific guys and say Omega and White are "the biggest megastars to come from wrestling". In order to 'come from wrestling' you have to have gone somewhere else. Did I miss a press release where Jay White was going to be third lead on a new Kelsey Grammer sitcom? Is Kenny Omega the new face and head chef of a chain of fast-casual fusion restaurants?
For a percentage of wrestling's dwindling audience, what Impact/AEW/NJPW/etc are doing is exciting and must-see TV. For another (probably larger) percentage, OMG CENA REIGNS BAY BEE. And I'm not saying you can only like one or the other. Then again, I'm not a Professional Sex Haver. The amateur ranks aren't bad though, and there's always shadow boxing.