Bench init command always gets stuck here and never initialises

Are you trying to install version 13?

there is a permissions error for user frappe with supervisorctl. You can try this…

erpnextuser="YOUR_ERPNEXT_USERNAME"; #it looks like this should be "frappe" from the screenshot
sudo usermod -a "${erpnextuser}" -G supervisor;
sudo perl -pe "s/^(chmod=0700.*?)$/;\$1\nchmod=0760\nchown=${erpnextuser}:supervisor/gi" -i /etc/supervisor/supervisord.conf;
sudo perl -pe "s/^chmod=0770$/chmod=0760/gi" -i /etc/supervisor/supervisord.conf;

and then re-run the production setup