The full text of this act (translated to English) is available here: https://www.jftc.go.jp/file/MSCA_Guidelines_tentative_translation.pdf

I haven’t read through the full text, but it does seem to specifically apply to only smartphones. The Switch is a mobile device but I think it’d be a hard case to make it count as a phone and a general computing platform like iPhone/Android.

Hmmm, I’m having a hard time choosing between the Seerup and Puxoca Coun. Does either come with a free side of Sseeiiqers by any chance?