A study released yesterday purports to find importance in the frequency of the he pronoun versus the she pronoun in American English, the obvious implication being the prevalence of male-focused sexism in writing throughout the ages.
According to this study, the ratio of male to female pronouns (he, she plus variations) stood at 3.5:1 in 1950, the larger number representing male usage, of course, which then swelled to 4.5:1 through the mid-1960s, when the sexual revolution set us all free.
The ratio now stands at 2:1 or less (that being the perhaps-outdated 2005 standard).
Now this is all well and good, but I think what it mainly shows is writers' ignorance of the beauty of using the plural form. They contains both he's and she's, and no one can ascertain the ratio — nor would anyone want to do so.
I cast my vote for plural pronouns — and nouns — when writing generically. The ratio, if there is one, will always be 1:1 when using the plural.