Seems like currently /etc/event.d/prefdm doesn't have the respawn flag. I suppose it should.
On the other hand, ,I guess one case were we shouldn't try to respawn is when the X server won't start (as in rawhide today).
This is needed. Old init would blacklist an entry after multiple crashes (foo is respawning too fast - disabling for 5 minutes). But now if I kill kdm, it is not restarted, which is bad.
You can set limits on respawn.
Fixing component, will have a fix here shortly.
Fixed in -12.