It’s “all” in the sense that it’s everything the instance knows about, in contrast to “this server” which is only content from users that are registered on this specific instance. Same concept as the “all” and “local” feeds on lemmy. I agree that a better name might reduce the confusion but I can’t think of a good one.
That’s the reason why I like C#, ASP.Net Core and EF Core so much. A simple CRUD app can be written in under 10 minutes and easily deployed in any form from a self-contained binary to a docker container to whatever eldritch horror lurks behind Azure or k8s. Personally, I run docker swarm mode for my stuff because it makes automated deployment super easy, kind of like a leaner k8s but if I wanted, I could just drop a binary on any windows, linux or macOS machine without needing to install any major dependency apart from my database.
Edit: of course, ASP.Net Core has its downsides too. Especially when it comes to auth stuff. I wish I could have something as simple as devise + cancancan in old versions of Rails.