The argument is kinda weak given how many kernel updates are there and how often they come (and kernel upgrade _requires_ reboot regardless of PID 1).
Re:Broken by design: systemd
by michaelmior on Monday February 10, 2014 @07:36AM
(#7210626)
Not necessarily. Ksplice[1] for example allows the kernel to be upgraded without rebooting.
The whole point of the article is that you don't need to upgrade sysvinit or another minimal /sbin/init like those found in the BSDs.