OT: "domain-level" email hosting services?

[Nathan Stratton Treadway]

On Sat, Oct 23, 2021 at 10:04:57 -0400, Patrick Shanahan wrote:
> I have done the same for >20 years.  but I do use relays for quite a bit.

Relaying outgoing email (i.e. what I sent out from Mutt running at home)
via my ISP's "submission"/port 587  service seems straightforward.

Do you also use "relays" for e.g. collecting messages arriving in from
the Internet, or anything like that?

Thanks.

						Nathan