I’m so confused. Why do you assume they are innocent just because they were born afterwards? Did they do teshuva?? How did they attempt to make ammends? Did they at the very least ask forgiveness?
All people are responsible for the sins and crimes of their ancestors so long as they have not taken any steps towards teshuva. That is also why we are responsible for the chet ha’egel, and that is why Mashiach did come in the days of Ezra, because they did not do a complete teshuva for avodah zara even though they were already the next generation. When we say viduy, we always acknowledge our fathers sins. Why? Is it just ceremonial, symbolic, or superfluous? It is an integral part of teshuva. It is absolutely fundamental to the process of atonement.
So yes, they are indeed guilty. And I suspect that are also proud of what their fathers and mothers did. If they have never even begged forgiveness, why would anyone think otherwise?
Don’t answer if you agree