Dude, that is historical true, Upstart was there before systemd , Redhat used upstart too. Then an RH dev created systemd and Arch,Fedora,Debian moved to system

Dude, that is historical true, Upstart was there before systemd , Redhat used upstart too. Then an RH dev created systemd and Arch,Fedora,Debian moved to systemd , Ubuntu followed Debian decision since Ubuntu is based on Debian and they share maintainers/developers.