As far as I can tell if you use a service like ImprovMX (not affiliated, just a customer), this shouldn't be an issue, because the email is forwarded by their s

As far as I can tell if you use a service like ImprovMX (not affiliated, just a customer), this shouldn't be an issue, because the email is forwarded by their service instead of your server. This page seems to suggest that, since they're filtering spam to protect their deliverability rates, not yours: https://improvmx.com/guides/emails-refused-spamhaus/ https://improvmx.com/guides/emails-refused-spamhaus/ This also seems like a fairly obvious fix for email providers, to detect forwarded mail and assign blame to the real sender? Idk.