Men shave, too and much more often (and these days, men shave more of their bodies, too). I've seen speculation that both sexes are trying to preserve an adolescent look. Men shave world-wide including in cultures where women do not shave and this goes back thousands of years. There's something in the human makeup that makes us want to remove body hair.
Many fashion trends, such as shaving, are as much about impressing other woman as they are looking good for men.
There's a controversy about Wonder Woman's arm pits. Some feminists are outraged that Diana shaves them. Here's some thoughts on that:
The character has been represented without excess body hair for decades.Ancient Greek Women removed extra body hair (NSFW). Wonder Woman's culture is inspired by the ancient Greeks.