My Stats 101 alarm bells go off whenever I see a graph that does not start with 0 on the Y axis. It makes the differences look bigger than they are.
The 'outsiders, gendered' which is the headline stat, shows a 1% difference between women and men. When their gender is unknown there is a 3% difference in the other direction (I'm just eyeballing the graph here as they did not provide their underlying data, lol wtf ). So, overall, the sexism effect seems to be about 4%.
That's a bit crap but does not blow my hair back. I was expecting more, considering what we know about gender pay gaps, etc.