In the end, what you need if you want really reliable self hosting is to own your own ASN and IP range, so you can tightly control the quality. Review how clean the addresses are before purchasing them and continuously review it for the duration you own them, as some been used for spam previously.
Unfortunately, you’re probably right. I’ve been self-hosting (email, web and DNS) for the past 10 years. So far, the only issue I’ve had was GMail rate-limiting my server when I had to email about the 30 members of a local voluntary group as part of secretarial duties. However, it made me aware that the delivery of emails sent by my server is more akin to a “privilege” than a “right” on the modern Internet.
By the way, I just upvoted a reply you previously made to another comment of mine: https://news.ycombinator.com/item?id=36032588 Thanks for providing that example of how homoglyphs can be used to “fingerprint” plain text. I also discovered that with Vim digraphs, I can easily input spaces that are look the same as regular space characters.
It's quite expensive, yes. But removes a lot of headaches (while introducing some new ones), is a great learning exercise and is most probably a solid investment when it comes to ipv4 at least, prices keep going up and it won't just disappear in the near future.
This is the way I think personally. I recently changed my mail server host, had to unblock the IP from MS and all that but since, it has been smooth sailing... for now.
