Could you try the command-line I used above while starting: appsupport-attach /system/bin/logcat | grep -E 'system_server|AndroidRuntime' ?
Also, I disabled the restarting of the runtime because it does not notice these crashes and just uselessly tries to restart without different outcomes (and heavily drains the battery as a result).
To prevent the restarts, do:
# systemctl edit appsupport@defaultuser.service
and then add:
[Service]
Restart=no
(To undo this, edit it again and remove those lines.)