No. A dichotomy is mutually exclusive and jointly exhaustive. Since there is no suggestion of such a relationship between women's rights and nudity no dichotomy is presented. Which therefor can't be false.
Poster is implying it's a dichotomy by pretending that better women's rights is proof that sexual expression has improved. The implication is that you either admit expression is better because we have women's rights or you admit you were wrong. False dichotomy.
> Poster is implying it's a dichotomy by pretending that better women's rights is proof that sexual expression has improved.
No, they are specifically saying that expression has improved because the improvements in women's rights are more important than the restrictions or regression of nudity. There is simply no dichotomy there. In fact saying that it is "more important" suggests that restrictions in nudity is also a factor. Again, not a dichotomy.
> The implication is that you either admit expression is better because we have women's rights or you admit you were wrong.
No, you can acknowledge that we have women's rights and still think we have regressed. But for that to be true you would have to argue what is more important than the improvements in women's rights. Otherwise you would be the one making a false dichotomy by claiming that things can't have improved because one thing hasn't.