The best way to resolve the question of who was right is to look for evidence that is not the expression of someone’s opinion, but is direct evidence from output. Evidence from production functions gives us such direct evidence. The available evidence from production functions uniformly indicates that women had lower marginal productivity than men.
Using census data to estimate the marginal products of men and women in the US in 1860, Craig and Field-Hendrey find that women were about 60 percent as productive as men in agriculture, and 40 to 50 percent as productive in manufacturing. Cox and Nye use data on nineteenth-century French manufacturing firms to estimate the marginal
product of male and female workers and find productivity ratios ranging from 0.37 to 0.63. When they test for wage discrimination, they find no evidence of wage discrimination.
Benjamin and Brandt use a 1936 household survey in China to estimate the contribution of men and women to family income in general and crop income specifically; they find that women contributed 62 percent as much as men to farm production.60 Women are also less productive than men in agriculture in developing countries today; Jacoby finds that women were 46 percent as productive as men in Peruvian agriculture in the 1980s. While the estimates of the productivity ratio vary depending on the industry and location, all of the estimates suggest that women were substantially less productive than men in manual labor.
Thus I conclude that women’s wages, at least in competitive sectors such as agriculture and textile manufacturing, were not customary in the sense that they were lower than women’s productivity.
Here is a previous post on this topic.