The Debian init system general resolution returns

The first releases of Fedora (15?) and OpenSUSE that came with systemd allowed switching between sysvinit (or upstart in sysvinit compat mode, in Fedora's case) and systemd. As systemd matured, both projects decided to remove sysvinit support to simplify things.

In other words, this is purely a downstream distro packaging / policy issue. Why do you think that there is an onus on "systemd people" to "understand" or "fix their implementation" here?