Inclusion is not an optional thing, developers must just fix their bugs instead of looking for excuses.
Besides it’d be more like sickle cell anemia or some other condition and letting them know it’s something the test just said they had, common in different groups, and inherited not a hyper polarized “tell them there skin color isn’t white so we can’t help at all” issue it was suddenly turned into. Not telling them about the situation they are in because they’re different than you is a horrible approach to communicating regardless what you plan on doing about it.
Yes we should inform all users about how existing systems are failing them especially if it's reasonably likely to cause them further problems in the future and yes we can do that without telling them they themselves are the problem and dictating the way they need to live. All it requires is treating them like a person when you talk with them and you can be helpful instead of blatantly insulting. Hiding that information from them only serves engineers not the users.
This also has nothing to do with "cultural misunderstandings" in the first place. Null is by no means some foreign concept name to the stereotypical programmer nor are common names exempt from causing problems. My name is Daniel Smith, it's actually so common it causes many problems in computer systems which use first + initial last name (shortened) + number because they didn't plan on having that many numbers - not to mention lookup confusion. You're specifically seeking a debate on engineers not being culturally aware when it's not even at play or even a requirement in the general sense of the topic.
It’s an extreme solution though. Not something you can ask of most people.