There's just more nuance to it than the way you and others on both sides in these comments are presenting it. There is an 16% gender pay gap, true, but it's actually a complex issue and just presenting that one fact in isolation leads others to believe "... and it is fully attributable to discrimination", which isn't the case.

Some of that is explained by "job choice" and choice of university degree, meaning women are self-selecting into certain lower paying jobs and fields of study. Like how women are underrepresented in STEM. This isn't to say women are bad at STEM. There are just societal barriers that prevent them from pursuing those career choices. Everything from the pervasive notion that women "don't like math" to harassment in male-dominated fields to our society enforcing the idea that women's role in society is to care for others - and the "caring professions" are not high-paying.

The gap is not wholly explained by these factors, and we should try to mitigate them while continuing to decrease gender discrimination. But don't pretend like these factors aren't also at issue. Meanwhile, the gap is closing due to women becoming more represented both in universities (outnumbering men in the US), various old-fashioned notions going away, etc.

There are plenty of studies that support this, I saw several both from Harvard (some of which I was familiar with) and many more from other reputable universities and institutions. Also some from irreputable, conservative think tanks - it's easy to see how this issue can be weaponized by them, but ignoring that job choice and other factors play a role is not helpful to closing the gender pay gap. This is from a US perspective, I can't guarantee it holds true in all "Western" countries - but I know it's the case in US and Canada

The US government has found that: "Specifically, differences in the industries and occupations where men and women work explain 42.0% of their variance in earnings. ": https://www.dol.gov/sites/dolgov/files/WB/equalpay/WB_issuebrief-undstg-wage-gap-v1.pdf (source on the chart in page 2 of the writeup, comes from 2020 study by the US Census Bureau). This is a sizeable effect and we should not ignore it.