People tend to forget that first party Ninty games tend to do well on ninty consoles. Arms isn't doing well because of its genre but because of it being a Ninty Ip and Ninty fans knowing what to expect (the games they've bought haven't disappointed them so they expect this title to do well too).
Mario Od. will sell well no doubt. It will not affect platformers one bit. Even if it does, the copies or games with similar elements will fail miserably unless made and promoted by Ninty.








