I never said that they are going to be forcefully rewritten, I meant that whoever maintains initscripts might eventually rewrite them using systemd units more t

I never said that they are going to be forcefully rewritten, I meant that whoever maintains initscripts might eventually rewrite them using systemd units more tightly because they are going be simpler and easier to maintain (in general, not because systemd is making anything any harder). You will still run something with systemd, this something can be the plain executable or an initscript, it is not like systemd checks and makes sure it likes whatever it is running...