Light Yagami's actions in the anime "Death Note" have a significant impact on the society depicted in the series. His use of the Death Note to eliminate criminals leads to a decrease in crime rates initially, creating a sense of fear among wrongdoers. However, as Light's actions become more extreme and he targets innocent individuals, society starts to question his methods and the morality of his actions. This leads to a division among the public, with some supporting Light as a hero and others condemning him as a villain. Overall, Light's actions in Death Note lead to a complex and thought-provoking portrayal of the consequences of using power to enforce justice.