[azornathogron]

Related: if you have a domain from which you never want to send email, you can also set up these records to tell receivers to reject everything.

Here is a guide: https://www.gov.uk/guidance/protect-domains-that-dont-send-e...

[flas9sd]

I like that concrete mail advice is two subpath levels deep into "the" UK government website. High text contrast, loads fast. Kudos to them.

[sk5t]

This is worth doing, as certain "vendor security vetting" services will check these settings on vanity/convenience domains they manage to associate with your organization.