The D stands for Deficiency in education
The whole systemD thing has always been an answer to a question that was never asked by people using Linux systems as a server.
It is nice that systemD might help laptops with their (de)hybernation issues.
They should start teaching in engineering school that simpler things are better, since they cost less to build and maintain, while being more robust at the same time. Nowadays everything is top-heavy from featuritis, costs a ton of money and is broken within 5 years.
People using Linux for serious stuff, are burdened with unnecessary complexity and the security risks implied by this very complexity.
Maybe mainstream distributors of Linux will start to learn that things which are not there, can't impose a security risk, and start publishing light-weight server versions of Linux. Really, nobody needs a windows Registry like start up system on Unix, the very idea should someone have banned from ever logging in on an Unix system.