I believe the interpretation is wrong here.

The hard data:

                         Employee Wages
                            F      M
 Has firstborn sons:      +0.8%  -0.5%
 Has firstborn daughters: +1.1%  +0.6%

The story here is that when men have children, in general, female employees wages go up, by pretty much the same amount. However, when the firstborn is a boy, they are harder on men, and a little more respectful of women.

I'd personally interpret this as men becoming more respectful of women when they witness their wives undergoing childbirth. However, the more drastic effect of child gender can be seen on male employee wages. I suppose the CEO might be channeling frustration in child-rearing a boy on his male employees.