Facts say the opposite. Whether it is education, crime, or poverty, there are huge differences between single-parent families and two-parent families. Even race doesn't make as much difference in outcomes. The poverty rate among black married couples is in single digits. The infant mortality rate among black married women with only a high school diploma is lower than the infant mortality rate among white unmarried women who have been to college.
None of this makes a dent in those who promote the big lie that one culture is just as good as another. What does it even mean to say that? Does it mean that facts fit the dogma? Or does it just mean that they choose to use words in a certain way? It may not make any difference in their theories, but only in the real world.
None of this means that one culture is better than another for all purposes. The cheap vulgarity and brutal ugliness of so much of our media is a legitimate complaint at home and abroad. The sheer silliness of our fad-ridden public schools is a national disgrace.
By the same token, cultures that are less advanced in some ways often have contributions to make in other ways. We all take different things from different cultures to create our own personal lifestyles. We need to stop pretending that it makes no difference when all the facts show that it makes a huge difference, from poverty to matters of life and death.