Unlike regular mailing list emails, emails to <listname>-owner@ are forwarded as-is to mailing list owners, which means they will probably be blocked later on as the mailing list email server is not the legitimate sender. This breaks SPF/DMARC. In my case, smtp-relay.gmail.com (which I use to emit mailing list emails) refuses to forward any such email.
I did not dig too much into ways to fix this because most (if not all) emails to these address are spam anyway, some of them passing spamassassin filters. But it may be better to do things properly at some point.
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Célestin Matte