Noah, for all that he “walked with God” did not have any impact on the people around him beyond his immediate family. They were the only humans he managed to persuade to join him.
After the flood, the Torah gives some rules (later known as the Seven Noah commands for humanity in general) to help regenerated humanity try to succeed a second time. This theme of a second chance, started with Adam and Eve, goes on to Noah’s flood and continues with the Children of Israel getting a second chance after the Golden Calf.
But why do humans mess up so often? Some people suggest humans are inherently evil. The Torah this week offers this alternative explanation. “There is an inclination (tendency) within the heart of humanity that is bad from childhood/youth”(Genesis 8.21). Notice it does not say this comes at birth but rather during childhood when one is influenced by external conditions.
In other words we are not born bad or good. We are born with capacities to do good or bad and these capacities are influenced by home, society and opportunity. The role of religion is to ensure that the other tendency, to do good and be kind, is developed and encouraged too. Sometimes it will overcome selfish egos but sometimes it will not. The Torah gives us advice but of course it is up to us to make the right decisions.