The goal of ARC is to improve deliverability of mail that passes through intermediary administrative domains, which given DKIM, DMARC, and SPF policies, might otherwise be quarantined, rejected, or silently dropped. Common examples of Intermediaries are mailing lists, alumni or professional email address providers like universities or professional organizations, et cetera.
If Fedora Infrastructure, as a forwarding and mailing list service, wishes to implement ARC http://arc-spec.org/ on the mailing list and alias forwarding servers, I have an OpenARC package review request open: https://bugzilla.redhat.com/show_bug.cgi?id=1615162
Thanks, Matt
infrastructure@lists.fedoraproject.org