What. I think you have your facts wrong about China. People were never forced to only have male babies. They had a one child policy for up until recently.
A consequence of this policy meant that most Chinese saw male babies more interesting for profit and the family than female babies. It didn't meant that female children weren't born, oh no, it just meant a lot of daughters were left out for dead, because they were not wanted by the family.
As a result, there is a very odd ratio between males and females today in China, and a prospected 19 million males in China will not have a female partner due to this irregularity.
The mentally, however, has since then been lessen (in part due to the government striking down on parents who do it), but also because females are becoming more and more useful, even in countries like China.
The writers may be basing the mentally of Leo Wong on this, but given how he doesn't live in China or that this policy was over a thousand years ago from his perspective, I would see it as unlikely.
Interesting speculation, nonetheless, but I think he is just average 'sexist'. Well, or just considers males superiors, males like these were very common back in the day.