>In an apples-to-apples comparison of women’s and men’s products with similar ingredients, however, we do not find evidence of a systematic price premium for women’s goods: price differences are small, and the women’s variant is less expensive in three out of five categories. Our findings are consistent with the ease of arbitrage in posted price markets where consumer packaged goods are sold. These results call into question the need for and efficacy of recently proposed and enacted pink tax legislation, which mandates price parity for substantially similar gendered products.

Later in the paper, they note that the 11% "pink tax" is actually primarily explained by differences in consumer preference. The supposedly really egregious one is razors, but women's razors aren't comparable products - they are significantly wider (which makes sense - we have more surface area to cover). This more or less matches with my life experience.

Not that women don't have gender specific consumer rights issues. But the real pink tax, I'd argue, is that tampons and pads are taxed as non-essential goods. That also has a much easier regulatory solution.