The gender wage-gap does not exist. What most people describe when they discuss the topic is the earning-gap, which seems like a semantic change but actually deal with the basic accusation of sexism being the reason for the gap.
Seeing as you didn’t cite the study you used (or that I’ve just missed it), I’ll use the study and analysis from Pew Research Center (http://www.pewresearch.org/fact-tank/2017/04/03/gender-pay-gap-facts/) from April of the current year.
Your use of data only take some aspects of the data into considerations. Take Pew initial statement, for example:
Based on this estimate, it would take an extra 44 days of work for women to earn what men did in 2015. (By comparison, the Census Bureau found that women earned 80% of what their male counterparts earned in 2015 when looking at full-time, year-round workers only.)
If you base your argument on only this statement, then you can only come to the conclusion that the pay-gap actually exists. This also cements your point about the gap being 81%.
Of course, Pew continued after that statement, and explained their findings:
Why does a gender pay gap still persist? In our 2013 survey, women were more likely to say they had taken breaks from their careers to care for their family. These types of interruptions can have an impact on long-term earnings. Roughly four-in-ten mothers said that at some point in their work life they had taken a significant amount of time off (39%) or reduced their work hours (42%) to care for a child or other family member. Roughly a quarter (27%) said they had quit work altogether to take care of these familial responsibilities. Fewer men said the same. For example, just 24% of fathers said they had taken a significant amount of time off to care for a child or other family member.
This is the earning gap, that has nothing to do with sexism but deals with decisions made by women that contributed to the gap. Although the analysis mentions that part of the reason may have a basis in sexism, it also illustrates that this sexism is also against men, not just women.
Your analysis is focused on biases, which are not measurable and therefore can’t be refuted. Your conclusions are based on that understanding that does not correlate to behavior and doesn’t take into account all the parameters that can form a complete picture of the situation.
Your arguments are in practice sexist, as they take away the determination, decisions, and behavior of women in the workplace and don’t allow them your support in being able to tackle challenges on their own. You even mention that “American women can’t wait for the trickle-down change” oblivious to the fact that if CEOs of companies are committed to that equal treatment, then perhaps those that don’t receive it might not be eligible for that pay-raise and might invest more time in other places, instead of the office. Are they not free to make that decision?
You also bring the Equal Pay Act of 1963 and suggest that it needs to change because it’s old and instead add another law that will remove the fairness of the old law. Something being old does not negate its relevance. Adding too much and defining something too much can also harm the fairness you want to achieve.