I've tried to self-host email for my domain a couple times over the past few years, and I always end up falling back to a paid host for this reason; I rarely use email these days, but when I do (or usually when I'm expecting an email from a recruiter or other business-related sender) I need some sense of confidence that it will go through correctly. The lack of ability to confidently send via self-hosted setup definitely feels intentional, which sucks.

Great article btw!

A lot of this is due to newness and perhaps bad IP reputation. You can fix the reputation by requesting your removal from blocklists. The newness should be fixed after a few years - have you run it on the same IPs for those 15 years? In my experience after a year or so the problems go away (admittedly this is on a much larger scale than personal email).