It’s pretty simple. Male/female are adjectives and man/woman are nouns. Referring to a person as an adjective that describes them is generally not a great look because it reduces the person to that one characteristic about them.
[Correct] Women who go shopping are female shoppers.
[Incorrect] Females who go shopping are woman shoppers.
It can be an honest mistake, but it’s used deliberately enough to warrant the side-eye, especially when people stand up to defend it. Some people do get a little weird about ANY usage of the word female, correct or not, but this is not one of those scenarios.
Don’t hold your breath…
If I could whip that out so quickly, imagine how it’s being spun in the maga echo chambers.