But, by dictionary definition, a non-average size woman s not "normal".
Adjective: Conforming to a standard; usual, typical, or expected.
Noun: The usual, average, or typical state or condition.
adjective. regular - standard - ordinary - common - usual
noun. normality - normalcy - perpendicular
It's not a value judgement, nor does it say anything about non-average being "unacceptable".
I had to think about why the statement "normal women have ___" bothers me. It's because, by definition, the opposite of normal is abnormal. While, I'm sure, that not everyone who uses such a statement means to imply that everyone outside that group is abnormal, that's what I hear. Abnormal isn't a compliment, IMO.
Either way, the statement involves a hint of body-shaming. Hopefully, that's not what the woman meant to do.
I can see someone using the term "normal" in this situation as a short hand way of saying:
I'm not especially thin and I'm not especially heavy. I'm not really pear-shaped or apple-shaped and I have an average sized bust. I'm not top heavy/bottom heavy. I'm not especially short or particularly tall. I don't have a long torso or narrow hips or a flat butt. I don't have a specific "problem" area that needs to be specially addressed in my hunt for the perfect pair of jeans. I'm average, I'm normal, I can't find a good pair of jeans to save my life.
But looking back at the original post, she does follow up "normal" with the phrase "not a single digit size". That does tip the sentiment into potential snarky territory. I still wouldn't address it, but the two comments together are not entirely innocent.