I think a lot of really big historical events are "forgotten" like this because they're so well-known. During the event itself, it's all anyone can talk about.

I think a lot of really big historical events are "forgotten" like this because they're so well-known. During the event itself, it's all anyone can talk about. After a few years of that, everyone knows everything they ever wanted to know about it and more. Due to over-saturation, eventually people get very bored of it. 10 or 20 or 30 years later, the subject rarely comes up because there's little practical need to discuss it. If a conversation does start, it doesn't last long. Even if someone has a story you haven't heard before, you have heard 100 others like it. It becomes almost a minor faux pas to mention it. You'll be seen as uninteresting. So people growing up during this post-event period just don't hear much about it. It was a huge thing, but it's like it doesn't exist. If they do hear something about it and find it interesting, nobody is too excited about explaining anything or answering their questions. So you've got one generation that knows a ton about it, and the next generation picks up very little of it.