You must not forget that many distros moved to systemd out of necessity rather than desire, and for some (Debian) the decision was lengthy, splitting and controversial.

EDIT: By "necessity", I mean things such as GNOME (which is a very often used graphical shell in a majority of distributions) and udev (which is getting integrated into systemd, is used by most distros, and, bar Busybox's mdev or Gentoo's eudev fork, has no alternative) depending or planning to depend on systemd.