My emails are often flagged as 'spam' for my recipients, notably on mailing lists. I've set everything up hopefully correctly (DKIM, DMARC, etc.) and I score 10/10 at https://www.mail-tester.com/ . I don't appear to be on any block list, and I own my domain (goffi.org) for over 20 years.
Any ideas what the problem might be?