Your narrative is embellished and does not correlate strongly with the data [1].

Embellished: marriage rates are 33.8% for Black women and 37.8% for Black men, neither of which I would round to 25%.

Uncorrelated: marriage rates dropped sharply among people of all single races on the Census except for Asians. It has dropped more sharply for Black respondents, but anything disproportionately affecting the lower and middle economic classes would disproportionately affect Black families.

Show me some data, and not outdated welfare policies from the 1980s, that supports the "social engineers" causal narrative better than plain deindustrialization. Or deindustrialization combined with good old American racism and mass incarceration. I am willing to change my position on this.

1: https://usafacts.org/articles/state-relationships-marriages-...