> then either you admit sexism is defined subjectively
That is indeed right in the definition, which you should read:
Hostile sexism reflects overtly negative evaluations and stereotypes about a gender (e.g., the ideas that women are incompetent and inferior to men). Benevolent sexism represents evaluations of gender that may appear subjectively positive (subjective to the person who is evaluating) but are actually damaging to people and gender equality more broadly
That is indeed right in the definition, which you should read:
Hostile sexism reflects overtly negative evaluations and stereotypes about a gender (e.g., the ideas that women are incompetent and inferior to men). Benevolent sexism represents evaluations of gender that may appear subjectively positive (subjective to the person who is evaluating) but are actually damaging to people and gender equality more broadly
https://en.wikipedia.org/wiki/Ambivalent_sexism