Let's test his idea on celebrities, who often become public figures because of their distinct physical beauty. Jennifer Garner and Ben Affleck have two daughters. Tina Knowles had Beyonce and Solange. Demi Moore and Bruce Willis have three daughters, as do Matt Damon and Luciana Barroso, who has another daughter from a previous relationship. Like her or hate her, Kris Kardashian has five daughters, and Bruce Jenner was a pretty good-looking guy before all that plastic surgery.
On the other hand, Gwen Stefani and Gavin Rossdale, who are both good-looking people, have two sons and no daughters. David and Victoria Beckham, both noted for their glamourous appearance, also bore sons. The late Princess Diana also had sons, but Kanazawa could argue that this was the case because Prince Charles is not considered "handsome." Women Most Attractive In Winter
As far as practical applications go, society has a long history of favoring sons over daughters, as well as beautiful women over plain ones, so it's unfortunate that studies like this perpetuate the idea that a woman's worth lies chiefly in her appearance, fertility, and propensity for bearing boys.