The adjustment of China’s fertility support policies should be contextualized within population governance modernization. Current policy implementation falls short of expectations, partly due to underutilization of China’s modernized population governance advantages and cognitive dissonance between policy subjects and objects, coupled with insufficient attention to evolving youth attitudes towards marriage and fertility and social mindset transformation. This paper proposes rectification paths. At the institutional level, a swift transition from “population quantity theory” to “population development theory” is needed. Policy evaluation standards should be established based on improving childrearing quality, guiding new-era fertility concepts, optimizing family-friendly environments, and promoting intergenerational integration. At the level of institutional mechanism innovation, we should leverage China’s “one core, multi-element” governance structure and regional fertility disparities to enhance overall fertility rates, targeting and promoting the conversion of fertility intentions among the childbearing population, transforming the advantages of population governance system into the effectiveness of fertility governance as soon as possible. At the level of promoting cultural concepts, we should address youth fertility challenges through continuous dialogue, emphasizing the integrated value of marriage and childbearing across societal, familial, and individual levels, while appealing to youth’s sense of responsibility through new cultural narratives on marriage and fertility.