Why are some people against women showing cleavage?

I seriously don't get it. To me it's a normal feminine thing to do. I grew up in California where I saw cleavage all over the place, and in school/college. There's fancy dresses that are stunning to see on women and the cleavage part makes it look even better. Tank tops, vnecks, plunge tops, etc. And who doesn't like boobs lol? I mean even other women have told me they appreciate beauty other women have.
Why are some people against women showing cleavage?
Why are some people against women showing cleavage?
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