In April 2014, Linus Torvalds expressed reservations about the attitude of a key systemd developer towards users and bug reports. In late April 2014, a campaign to boycott systemd was launched, with a website listing various reasons against its adoption.
In an August 2014 article published in InfoWorld, Paul Venezia wrote about the systemd controversy, and attributed the controversy to violation of the Unix philosophy, and to "enormous egos who firmly believe they can do no wrong." The article also characterizes the architecture of systemd as more similar to that of svchost.exe, a critical system component in Microsoft Windows with a broad functional scope.
Just seems like classic "compare any software I dislike to Windows" kind of stuff, but I'd love to hear from someone who is more familiar with it.