Unfortunately, as long as education is not funded appropriately and museums and historical programs (like a lot of what the national park service does) are defunded, this problem will continue to get worse. We also have the cultural issue of acting like history is "boring" and not worth learning, but it's literally what helps us understand where we've been and why things are the way they are.
People who have experienced things personally are a wonderful reminder, but their deaths are not what causes this. These people have shared their stories time and again, in books, museums, documentaries, etc etc. It's that the majority of the population isn't interested or aware, and that breaks my heart.
