Comment by nomel
I had a great Windows firewall like this about 20 years ago. It would pop up a dialog for every network request from an app. You could block or allow based on port or destination, or "block all". It was amazing, because as you say, it made it very obvious when an app was trying shady shit.
I would love to have that back, but I was never able to find a firewall so hostile to the user experience of the general population.
It sounds similar in spirit to Little Snitch, mentioned in the article (on macOS, but which inspired OpenSnitch, which runs on Linux). It is awesome indeed, if a bit overwhelming at first. Most regular users would just uninstall it to avoid the constant barrage of requests initially, and then every time a new piece of software tries to connect to anything.