CEDX and NSMBWii really are nearly idendical in how they played out in catalysts for each mascot’s respective “dark age”:

-NSMBWii outselling both Galaxy games combined
-CEDX having it’s weird FOTM status online, completely outselling and overshadowing both GA tie-in titles by a landslide

The constant NSMB comparisons I’ve made for years also has to do with the fact Nintendo never intended for it to overtake Mario’s main identity, let alone become it’s own subseries. It’s eerily similar to how Bamco clearly were still holding onto a fair bit of World’s influence until GA bombed.

It really was a “New Super Mario Bros.” situation which equally got out of hand in a similar fashion despite initially having good intentions from the start.

Although I’d argue NSMB1 was still far more unifying as it didn’t just purely rely on NES nostalgia like it’s sequels ultimately did.