pacman-init.service exist in Arch Linux and its derivatives, where Calamares often used.
This service does not exist in other distributions like openSUSE, Fedora.

diff --git a/src/modules/services/services.conf b/src/modules/services/services.conf
index 50069e6..fd3e398 100644
--- a/src/modules/services/services.conf
+++ b/src/modules/services/services.conf
@@ -12,9 +12,5 @@
   - name: "graphical"
     mandatory: true
 
-disable:
-  - name: "pacman-init"
-    mandatory: false
-
 # Example to express an empty list:
 # disable: []