A partir dos documentos em coredump.conf ,
To disable a configuration file supplied by the vendor, the recommended way is to place a symlink to
/dev/nullin the configuration directory in/etc/, with the same filename as the vendor configuration file.
sudo ln -s /dev/null /etc/sysctl.d/coredump.conf
sudo systemd-sysctl
Desde o systemd, as coisas são gerenciadas de maneira diferente.