Smash Bros has so bad netcode that serious competitive online play does not really exist. This is why most big fighting game tournaments dropped smash during covid due to being forced to be ran online (and Nintendo is just a real pain to work with). Instead we get some previously "small" game being ran at big tournamets like Skullgirls at EVO because they have rock solid netcode so they can actually be played online at high level.

Also smash is played on consoles that prevent one from installing cheats basically the fact that the whole platform is fully locked down is the anti-cheat. Still controllers are sometimes checked at tournaments for any additions that can run macros (most adapters that allow one to use a different consoles controller can do this)

And it has barely limped along over the years in comparison to other developer supported FGC games.

This is more of an "exception that proves the rule" since Smash is pretty much the only competitive game with zero centralized support that has broken out of a tiny niche to compete with big names.