I think that the "tights are not pants" and "leggings are not pants" arguments are used in classist and body-hating ways in Australia - the judgement is usually applied to young working-class women (it used to be "don't go out in your tracky pants" until expensive sportswear showed up) and/or fat women and/or working-class older women who are not being "classy". While there are definitely fashionable, thin young women who wear tights and leggings as pants, they're not the ones who are criticised for it (and I say this as a person who has been publicly mooed at while wearing leggings under a knee-length dress!)
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