No, there is no excuse. It's something that people should know and is generally pretty common knowledge.
That has nothing to do with how you act towards people who don't know who are otherwise well intentioned.

When you react to ignorance with hostility, you don't teach people not to be ignorant, you teach them not to ask, that it's better to be confused because people who know are angry and will make you feel bad.

You can't shame someone into being better. Shame only tells people what not to do. When someone asks a question out of ignorance, reward them with kindness and information. We want people to educate themselves on what they don't know.

It's good to be vigilant for ignorance and implicit bias, and it's better to handle it in a way that sticks.

You want the person you're informing to say "d'oh! 🤦", not "I'm sorry. 😔"