There probably has been a lot of discussion about this item in the manosphere, and some moralizing about pornography by Christians as well. Porgnoraphy is a bd thing, the act of making it is bad, the industry, and so on. But who gives a better explanation of the decreasing interest in sex, marriage, and reproduction? Are anti-pornography Christians ignoring what industrial mass society has done to men, depriving them of their masculinity while treating them as mere consumers? Herbs who do not have much interest in women (and in turn are not so appealing to women) or in being subservient to the system, but know of no other alternative? And what has been the effect of industrialization (not necessarily Western feminism) on the personalities of women, who now have the means to be independent consumers, even if they are not more "career-oriented"?
When men have few opportunities to exercise their initiative, or to have an amount of control over their own lives that would enhance their self-respect, why shouldn't they turn to video games or other pleasurable pursuits that don't remind him how much of a failure he is? (And why bother to make an effort to even fornicate with women who aren't attracted to them or won't consider them a priority in their lives?)
While there are Chinese women who lament being "leftover women," I have not seen any media coverage of single 30-something Japanese women and their situation.