[Firadeoclus]

Should the price of something depend on the amount of work done? On how much the buyer values it? Or on the amount the buyer has to offer to outbid others?

Does an employer just pay for work done, or possibly also for availability, potential, loyalty, goodwill?

Edit: That said, I absolutely agree that gender isn't something that should figure in those considerations. At best it's a poor proxy for much more specific differences between individuals.

[knowThySelfx]

I agree its not easy to quantify wage rates. It is highly context dependent. The valuation depends on many things. Still gender should not be the parameter since valuation depends on an individuals performance.