Oh for fucks sake. No wonder this study is ridiculous. It's an economist trying to make inferences on mental health. The only actual data he had is a correlation in mental health diagnoses and women earning significantly* more. (Number not defined)
He has no evidence for causation. He does no work to get rid of confounding factors like toxic masculinity's famous dislike of therapy. He just sees a rise in the pure number of diagnoses and says women earning more is bad for the mental health of both people in a marriage. He doesn't even bother to check what the diagnoses are, or look for any kind of severity. For all we know the finding here could be that women who earn more and men who are willing to be with them seek counseling earlier than couples where the man makes more.
This is shit science.