Availability of Sysvinit does not mean you can use it as safe as systemd , there is no requirement for Sysvinit support in debian package's anymore , so if you

Availability of Sysvinit does not mean you can use it as safe as systemd , there is no requirement for Sysvinit support in debian package's anymore , so if you want use Sysvinit then you maybe encounter some package which does not work on debian.