Japan is a country that frequently practices the death penalty.

Death Note would have a gash plot if Japan didn't like a bit of punishment that wasn't compatible with life.

Admittedly, I'd be much more likely to write in the Inconvenient Note so arseholes would find themselves wearing wet socks every day; encounter people who never finish their sentences; have to find a towel lying about the house before showering; or have every underfoot surface feel like a box of Lego.

the Japanese state doesn't want to ban the death penalty for the same reason why it celebrates the genocides it committed against its neighbors. it's a very useful tool to keep people passive against its abuses