You know this is funny, I remember reading comments EXACTLY like this about 3-4 years ago but with pulseaudio in place of systemd.
Pulseaudio was Lennart's previous project. It broke everything in linux sound for a while, everybody moaned and hated it and said it was the worst thing since the crucifixion of Christ.
Yet, name one problem you had with sound on linux in the past year? There are very few. Pulseaudio now just works(tm) and is a unseed, unheard of part of the plumbing.
If you remember what is was like messing with ALSA and (shudders) OSS before pulseaudio came along you will agree that the current state of affairs is a million miles better. It used to be really difficult to get more than one application to be able to play sound at a time. I remember compiling sound drivers from source just to get them working. Configuring ALSA config files to get surround sound working was practically a black art. Creating manual scripts that unmute the sound card on every boot because the driver didn't initialize it properly.
With pulseaudio, I never have to worry about any of that and configuring surround sound takes me two clicks of the mouse.
Lennart did a fantastic job with pulseaudio, he took on a dirty problem that nobody else dared to touch and went through years of criticism to produce a really high quality solution that solved the linux audio problem so well that you don't hear complaints about it anymore.
In light of that, I trust him to do a good job with systemd. It'll be a couple of years of everyone moaning and bitching and whining about it, then one day it will have become a seamless part of the plumbing, everyone will take it for granted and wonder how they ever managed fighting with shell scripts and fragmented init systems before systemd came along.
It's ironic that Lennart Poettering is probably the most abused developer in the entire OSS ecosystem, yet he is one of the people contributing most to it. For our sake, I'm glad he has such a thick skin. If I was him I'd have quit this game long ago.