[thwarted]

And the only thing keeping that from happening with traditional init is someone submitting a patch against the package to split up the functionality of the init script into more distinct subunits.

It's interesting to note that no patch has been submitted against the sendmail package, most likely because it's unnecessary. And the only reason that the logic was moved to separate subscripts called in ExecStartPre entries for systemd is because systemd doesn't have a language to express those things in, so they need to be subscripts in order to have that capability at all.