One of my friends is a woman of color, and not that long ago, she arrived with three male colleagues in the lobby of a building for a scheduled meeting. The administrative assistant came out, walked right past my friend, shook the hands of the three men, and welcomed them. My friend extended her hand to introduce herself, and the assistant asked, "Oh, you're with them?"
My friend is head of the department.
In the aftermath of the incident, there was an apology, but along with the apology came a number of excuses: The remarks were unintentional. There was no malice intended. Even the apology itself was a "I'm sorry you felt this way" non-apology.
Episodes like these are the sort of slights that accumulate over a career, and they contribute to an unwelcoming climate for women in the workplace. Kieran Snyder interviewed over 700 women who left the tech industry. Almost all of them said that they enjoyed the work itself. It was the work environment that drove them out. And six out of seven have no plans to return.
This is hardly a topic I have expertise in, so I'm going to defer to this thoroughly-researched article by Rachel Thomas. For me, the part that stood out was this: "a study from Yale researchers shows that perceiving yourself as objective is actually correlated with showing even more bias."