systemd is not monolithic. Many of its features run in processes other than PID 1 and most of its advanced functionality can be disabled with compile-time configuration options and/or at run-time.
And besides, I don't even care whether it's monolithic or unix-ish or whatever other labels you'll come up with. What I care about is that it is faster, more reliable and more powerful than any of its alternatives. And unlike you, Poettering posted long and detailed rationale for the systemd design in his blog, while you completely fail to give any technical arguments against it. That makes it a lot easier to agree with him than with you.