I think it's more of the latter.
When looking at Zenyou, the lab monster, you see that aside from some rage stuff(reverse Super Jump Punch, some of the dair/fludd stuff) and new kill setups(reverse fadeback nair dsmash, the 50/50s from Dair, etc) a lot of Mario's discovered setups and cool tricks are just that; tricks. Useless gimmicks.
I honestly can't see Mario going very far. The character is one that doesn't have the tools to deal with certain qualities like massive disjoints, camping, and being outzoned. Mario isn't a Sheik, Diddy, Fox, Rosa, or Sonic. The character just can't adapt to a lot of situations, which is why you see Ally trying to "impose his will" on other players instead of playing the matchups.
Just wait until people finally learn they should be fighting him like this:
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