Terminal Trove mentioned Matt Hartley's `netwatch` tool as its "tool of the week:" netwatch is a network diagnostic tool for the console, and it's pretty comprehensive, showing a ton of information about network traffic in a quite reasonable, useful interface.
RasKrebs' sonar is a CLI tool for inspecting and managing everything listening on localhost ports. The name is overloaded, and badly, but the tool works well. So they built something more suitable for their purposes. sonar list gives you ports, process names, Docker container names, Compose projects, CPU/memory usage, and clickable URLs in one shot.