At the college level it is motivated by scholarship rules given Title resctrictions.
They need women’s sports that men don’t participate in in order to balance the inoordonate number of scholarships that the football programs provide.
This also helps reinforce the feedback loop that keeps women’s baseball from overtaking softball as a preferred sport since so few girls coach or play it relative to softball.
Softball itself exploded in popularity when (like Iowa’s famous 6v6 basketball) there was a serious belief that strenous activity could damage women’s bodies and the sports they played needed to be limited.
That’s largely been found to be bunk, but the legacy of ‘modified’ sports like softball lives on in the extracurriculars most commonly available.
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