If that were to happen, then masked wrestlers would become the norm and at that point, they wouldn't be special anymore, right? And back to Square 1 it is. It's a dog eat dog world nowadays where if you don't have any interesting quirks, you're done. If everyone, who's under the audience's radar, is given a mask to work with, then not only does that pool them together with other rejects but you've effectively restricted their chances to express themselves because the mask is supposed to do the talking.
And besides that, I doubt it'd work with wrestlers who've already debuted. Once you've gotten a taste of how someone is, you generally retain that opinion of them unless they're totally repackaged and like I've already stated, a mask won't do it at all. Added mythos? Perhaps but that's where it ends and even in that case, it's pretty shallow.