It is weird to name something as a "massive simplification" when saying that it is intended to replace "plain and simple config files". "Massive simplification" is a term that may be applied to something like the daemontools of Bernstein and to other systems inspired by it, but certainly not to anything based on systemd, where it is much harder to discover what it really does, when problems appear.

Perhaps systemd has "security advantages" over alternative solutions, but I have never heard of them and I cannot imagine them, so please name them.