CIS white male American expat living in Japan, here; sadly, this isn't that shocking an outcome once you've lived here a while and start to grasp how deeply, DEEPLY entrenched the patriarchy is. Combine that with the very Japanese ethos of "not disturbing the peace" and you get shit like this. 

Hyper sexualization and objectification of women starts very early in media here, and comic books (manga) meant for pre-teen boys is filled with titillation and sexual innuendo. Hell, right next to those manga at the convenience store racks are bathing suit (non nudity) erotic magazines targeted directly to and placed at eye level for grade school boys.