The issue isn't so much in the medium (shell), but the underlying program itself (sysvinit) being overly primitive. See the daemontools family where runscripts are largely as short or shorter than systemd unit files: http://homepage.ntlworld.com./jonathan.deboynepollard/FGA/ru...
In addition, the BSDs have much shorter rc scripts mainly by putting all the boilerplate functions into a single library file that is then sourced. Gentoo's OpenRC framework, as well.
Franly i find myself thinking that moving the boilerplate elsewhere is also what systemd and upstart does. But those implement it in C rather than shell script.
In addition, the BSDs have much shorter rc scripts mainly by putting all the boilerplate functions into a single library file that is then sourced. Gentoo's OpenRC framework, as well.