The main issue is that playing SD Remix isn't nearly as convenient as playing something like P:M which only requires an SD card. If the name tag exploit somehow got to the point of allowing us to play SD Remix, it would have a chance, but even then there are still other factors to consider (such as Nintendo's support).
Most people in the community don't particularly value a well balanced roster
Not calling your post negative, but I find this is to be a somewhat back handed/speculative comment.
While I would agree with the notion that imbalance can make a game more appealing (I mean, just look at MOBAs), I think what players truly value are some kind of contextual rules where ideas and concepts are recurring throughout the game (i.e. fastfallers are easily combo'd, shoryuken-esque recoveries suck w/o double jump, etc.). While this kind of normalization makes the strategy and inter-character relationships more simplified, the removal of niches makes the meta significantly less archaic.
This becomes even more evident when you consider how many people complain about playing vs. Jigglypuff. Characters such as Jiggs and Ice Climbers stand out because they don't fit in the same mold as the rest of the cast [both viable and unviable]. This isn't to say other characters don't break rules (shines, float cancelling, etc) but they don't break enough to be considered "gimmicky" or "niche" and, thus, don't require niche experience to comprehend.
Another way of looking at it is through the Melee ruleset. We use four stock, 8 minutes, but our average match time is probably 3 to 4 minutes. Why is that? Would that change if characters who bring that average down significantly (such as Fox, Falco, and Falcon) were played less? If they were played less we'd probably change our ruleset.
TL;DR/Conclusion: People don't dislike balance, they dislike niches. More viable characters can disrupt normalization.