But the init system was Upstart. Upstart, like SystemD, can start daemons from SysV scripts. At the time, the majority of distros still used SysV or SysV-like i

But the init system was Upstart. Upstart, like SystemD, can start daemons from SysV scripts. At the time, the majority of distros still used SysV or SysV-like init systems. As long as the newer systems had backwards compatibility with the SysV scripts and the newer functionality were not needed, why would upstream switch to the new format? SystemD has managed to gain near-ubiquitous usage, to the point where plenty of upstreams now only ship systemd unit files, but I would argue that this change was first initiated by the introduction and adoption of Upstart in both Ubuntu and RH.