Erhm... No, this guy played online BEFORE the release date.It's on reddit:
https://www.reddit.com/r/3dshacks/comments/5dujk2/psa_sumo_bans_still_rolling_out_caution_for_those/
Well, taking away online gameplay because they have been known to use the leaked game, which is violating Nintendo policy, is legal. They have already proved only hacked 3DS devices are the only devices able to obtain the leaked copies of the gamse. So, they are in the clear to give out bans.