As for your question: everything is being shoved into one piece of software. Windows could be viewed as a humongous base package with very little customization or choice (extending far beyond the current state of GNU/Linux including systemd). Systemd is being perceived as limiting people in choice as it seems to handle more and more features.
Systemd is currently:
sysvinit + udev + consolekit + cron + anacron + syslog + logrotate + various network scripts (+ dhcp client/server) + time server
This kind of departs from the idea to have seperate daemon's / software handle specific and well definied tasks. And to handle these well.
However, systemd can still be stripped to a bare minimum of sysvinit + udev according to it's developers.
I *am* starting to wonder: when will it end? Eventually it might become too big and end up like HAL.