once you have a domain you now have the ability to own stuff online. that is, independent of any corporation. The main benefit this gives your average person is the ability to move email around between server providers. but you can now have a web presence that is not (facebook, twitter, hackernews). nothing against sites, they are fine, but it is nice to have an online existance that is independent of them.

Unfortunately the bar is a bit high for most to realize most of this. I miss the days when your isp would offer web, ftp and email hosting.

It's good for having your own website. That's super easy to host and use.

It's quite another thing for email. While it might not be that difficult to set up a basic email server, but to actually get it set up all correctly, and secure, and whitelisted, and get anything else on the 'net to actually interact with it is a little less trivial. And an email server that can't effectively send email (that won't be ditched along the way by some anti-spam measure somewhere) would be pretty limited.

Maybe useful for receive-only stuff like password reset links or one-time authentication links though?

You can host your email with your own domain with one of several services that take care of all the details (mailgun, fastmail, protonmail, etc), If you have problems with the provider you change your domain configuration to a different provider. Does ot solve all the issues but it is more flexible.

You don't have to self-host it, you can point it to an email provider (Gmail, Fastmail, Zoho...) and let them do the hosting for you. If they ban you (like Google likes to do), just point to another service and keep your email address (and therefore access to other services).

I work as a sysadmin and I don't want to bother with self-hosting my own email. I happily pay someone else to do that for me.

You can give unique throwaway addresses to people you don't fully trust (e.g. newsletters, recruiters) and apply the rules you want. It would be very naive to think that Big Tech won't abuse their market positions.

I do this, and it's very nice to tell who lost/sold my email.

Also it's funny to see people react to their business name being in my email :P .

I had a website break, because they were filtering emails that contain their domain name for some reason.

And I had no way to apply for the government licence thing I needed, and the people on the phone suggested I use the website.

I’m very rigorous about including the full domain name in my email address (consistency helps me remember what I used. I made the mistake early on of using [email protected] instead of myname-paypal.com@… and it drove me insane until I changed it), but every once in a while there’s a site (or occasionally a customer service rep) that refuses to accept that, in which case I just make up some unique three letter suffix to use instead and make a note of it in my password manager. My email for my kids’ school whose name starts with a W, for example, just ended up being [email protected]. Luckily these exceptions are rarely necessary and I’ve only had to do half a dozen of them in about 17 years of doing this.

Yes, I got once a discount because the phone agent thought I am a colleague :)

I've had a few occasions that employees thought I worked for the company based on my email.

On one occasion, I was checking into a Hilton hotel and the employee thought I worked for corporate due to my email, [email protected].

In the past, I used to explain to them how I control the domain and I have separate emails for every company due to spam reasons. However, this usually caused confusion so now I sometimes go along with what they think or hint that I'm some 'mystery shopper'.

My Gmail is my throwaway address, if something is important I use my real address (selfhosted).

Fastmail offers this feature as well, for less technical users.