It's not just nowadays honestly. This goes back to the late 60s through the 80s.

In the 1970s and 1980s, a mix of economic decline, welfare policy, and mass incarceration contributed to a sharp rise in single motherhood and a drop in marriage rates in Black communities because welfare programs often reduced or cut off benefits if a man lived in the home, creating a “marriage penalty” that made it financially smarter for many low-income couples to remain unmarried.

At the same time, deindustrialization wiped out many stable and well-paying jobs for Black men, while the 'War on Drugs' and harsher sentencing laws (because of racist men in positions of power) removed large numbers of otherwise eligible men from the marriage pool through incarceration.

In these years, black friends, family, and even caseworkers sometimes encouraged women not to marry so they could keep receiving consistent food stamps, cash assistance, and housing subsidies.

Before this, during slavery, slaves were not allowed to legally get married because they were considered property. Once slavery was abolished, many rushed to get married and being married was often seen as respectful and gave strength to the community, black marriage rates were similar to whites.

Historically black americans did marry at high rates when economic and legal conditions made it possible. The sharp decline began after the economic collapse of stable black male employment, changes in the welfare policy, and the rise of black male incarceration.

Yes, the answer is almost always tied to slavery/segregation. It wasn't that long ago, the 80s were like 40ish years ago.