[benou]

I'm self-hosting for 17 years and counting.

In my opinion, the pragmatic solution I use is:

1) use a specialized distribution (I use yunohost but there are others). This makes configuring SPF, DKIM, TLS and more a breeze

2) use a reputable relay to send your emails (I use OVH but again there are plenty of other choices)

Of course it means you are not "pure" because emails you send will go trough a 3rd party (the relay) but it solved the delivery issue entirely for me, so that I can continue to benefit from all the other benefits of self-hosting.

[MaKey]

I'm self-hosting my mail server without a relay. It is still possible, you just need to be persistent. In the beginning Microsoft might just let your mails vanish and while they won't confirm this when you contact them doing so eventually resolved my delivery issues with their mail servers. With Google I didn't have any issues.

[constantius]

Do you run Yunohost in production? Did you consider Cloudron/Coolify/etc.? I use Yunohost for personal services, it's extremely robust, but has a few lacking features that you'd expect to have in more professional setups.