This seems like a no-brainer to me. I've attempted to set up my own email server for personal use multiple times. Even with fulfilling the tablestakes of SPF,

This seems like a no-brainer to me. I've attempted to set up my own email server for personal use multiple times. Even with fulfilling the tablestakes of SPF, DKIM, and DMARC etc, I always run into at least one major email provider blocking all emails from me specifically because of who I host my VPS with. Outlook in particular seems to aggressively block all SMTP communication with both DigitalOcean and Linode. As an individual, there's nothing I can do about this. I've just resigned myself to either not being able to not communicate with email addresses on Outlook, or use an alternative email address for those rare occasions.