Memes

Do you mean that just like we have defined inch the length that is exactly 25.4mm (where mm is the length light travels in 1/299792458 seconds in a vacuum, seconds being whatever the fuck they are), we have also defined animals with XX chromosome females, and if they’re human, women, while recognizing that there are rare exceptions?

Two things:

A) you're not thinking procedurally. Doctors do not generally check chromosomes when they determining sex generally. So it would be more accurate to say "in infants, doctors define sex by looking at genitals, in adults, by looking at a variety of characteristics. We use chromosomes in medical circumstances to look for potential conditions that may explain symptoms, and sometimes we can use that as a category in determining sex" The definition you are using is really most applicable in people who are doing research, not clinical work, or interacting with human beings in a social context.

B) cool, so we've established that is what you think sex is. Other communities define sex differently. You can't claim inches are some universal innate biological truth and those heathens over there using centimeters are wrong and need to accept the wisdom of inches. And while inches might be more useful to you, centimeters may be more useful to them.

I would really suggest that you read “Bodies that matter, on the discursive limits of Sex” from Judith Butler. She literally has a PhD in philosophy and has devoted her life to analysis of the way we as a society conceptualize sex.