And even after controlling for all those variables, there is still a wage gap.
Which there have been plenty of theories as to why and by how much that variance is. The key is that the variance isn't 23% or anything else ridiculous like that. It's more in the ballpark of 3-6% or such.
Men act differently than women. This is a fact. It is also different in each industry - with some jobs have the wage gap being in favor of women. But just in general - some things that can definitely play a factor in the wage discrepancies would include:
-Men are more likely to move jobs. I can tell you this myself - my wife loves to complain about her work. She has moved 0 times since she got her job out of college. I've moved 3 times, my pay has since quadrupled over the years from when I started my first job out of college.
-Men are more likely to ask for a raise, or ask for a higher starting salary. I've argued my starting pay for all of the jobs I've taken.
-Men are more likely to push/ask for promotion.
Plenty of others I'm not thinking of at the moment, but you get the obvious point.