Well, consider I’ve run my own mailserver on one of those domains since 2001 so I’ve had plenty of time to “grow” with it. I have no issues with GMail and the like but as I said my domain has been around a long time and so I may well be grandfathered in a lot.

Having said all that, even with my newest domain (less than a year old) I don’t have any issues so long as I make sure to comply with all the caveats around ensuring my MX records are good, making sure my DMARC, SPF, DKIM and even PTR and reverse DNS records are all in place (the latter is one a LOT of people forget when self-hosting but reverse lookups are a big deal with mail). The amount of mail that my mail server spam-buckets from domains with only forward lookups and no reverse is astounding. But having said that it’s a GREAT way to block spam.

Finally, mail on residential IP blocks or even a lot of cloud provider blocks are just plain not good for mail hosting. One of my MX hosts is on a Linode which gets blacklisted periodically in one of the less reputable blacklists, but it usually doesn’t affect mail flow all that much. I do subscribe to services to monitor for blacklist listings and delistings for my IP’s as well mostly to keep track but it’s handy to know if there might be something wrong with your mailserver.

Mail hosting isn’t for the faint of heart… but once it works it pretty much just works. My primary personal domain I haven’t changed anything in a couple of years… and I’ve had no need to change much with the mail server itself. It comes out of the box with some nice secure settings and it’s kinda nice to have two decades of mail I can refer back to on an IMAP server :)