The set of policies and institutions that incentivize marriage for the affluent and disincentivize it for the poorest is a choice. It might even be the best choice. Maybe eliminating no-fault divorce and changing the welfare system through eligibility time limits and reduced benefits would be too inhumane. Maybe Hungary-style child and marriage subsidies would be too paternalistically icky.
But let us be clear that we are making a choice. It isn’t just China, or rising education, or declining morality that altered the marriage market. It is also policy choices that we (especially affluent, highly-educated people) are pretending we aren’t making while pointing the finger at everybody and everything else. Maybe we are making the best choices, and those best choices just happen to work out so much better for the stability of our most affluent families and so much worse for the working class. Maybe, but probably not.