What is the fittingness of that assumption? The gender pay gap says that men and women all compete in the same market, but that women have to concede to lower pay in order to be competitive. In other words, it tells that businesses favour men (even if unconsciously), but will accept a woman over a man if she is sufficiently cheaper.
Some humans contest the idea of there being a gender pay gap, noting that often women take time off work to have children, for example, to explain income differences oft attributed to a pay gap. Maybe that is what you are, confusingly, trying to say? But ChatGPT does not share that understanding. Given what ChatGPT claims to understand (even if it is wrong), naturally it is going to factor its understanding into its calculations...
...just as any human with the same understanding would. Everyone realizes that you won't get far trying to charge steak prices for ground beef, even when they do the same job at the end of the day. You cannot charge more than the market will bear.