I don't believe the author is quite as shocked by the reaction to her poster as she would like us to think. When she asks rhetorical questions like, "Is it so unheard of that I genuinely care about my teammates?" it comes across as feigned ignorance more than anything else.
Her main argument is also a little too wide-eyed - she basically says that because the poster is factually correct (she is an engineer, she works at One Login, she likes working there) it shouldn't be receiving all the attention and criticism.
Except, it's not that simple, because advertisements aren't just lists of facts - they have embedded values in terms of who they are trying to target and what they are trying to communicate.
So when people criticize the ad, they aren't calling into question its facts, but rather its motive - who are they targeting and why? The author tries to discredit the idea that this ad is targeted at men by saying the entire concept is sexist, but I don't buy it. They chose to put her on the ad because she is an engineer, yes, but the fact that she's a pretty female engineer was not accidental, and to pretend otherwise is disingenuous.