OP linked to an entry in their newsletter. If you check out their site, they are being pretty clear that they're in the business of "Independent technology for modern publishing", stating in pretty big letters that "Ghost is a powerful app for professional publishers to create, share, and grow a business around their content. It comes with modern tools to build a website, publish content, send newsletters & offer paid subscriptions to members.".
Reading their newsletters would get boring fast if they started every single one of them with repeating what they are.
I think this is going to be pretty huge.
I ended up subscribing to @feed@404media.co (404 Media) after following them on Mastodon. It just feels like a more direct way of following media that fits with how I consume stuff online these days.