Nintendo's AP page (which is legal facing and written by lawyers, rather than public facing and written by/as PR) now defines SX and SX OS as a piracy tool for DRM circumvention. It is not even remotely defined as homebrew tool (note, Nintendo makes no mention or classification for other CFW options as they are purely software and, for Nintendo, probably considered insignificant compared to a packaged good).
YouTube won't side with the user, the tool is strictly illegal by Nintendo's definition and would violate YouTube's policies as it shows DRM circumvention, regardless of whether or not you show it being deliberately used for piracy (and when common sense says 99% of usage is piracy). Until someone challenges Nintendo to a court case (be aware Nintendo has been winning a ton of flashcart cases all over, and they classify SX/OS as a similar tool so they have precedent in market's they've already won in) and prove otherwise, SX OS is basically poison.