Then since it is a full programming language REPL, not only you have text, there is also structured data to act upon.
On top of that comes the capability to directly access dynamic link libraries, the libraries of the language being used, and when the OS exposes it, application automation APIs.
So you can do stuff like select an open application, or something inside it, then switch to your REPL and execute some script over that selection.
Basically you open something like Jupyter Notebooks on the OS, and interact in a graphical way with everything that is running, not just executables that can only talk text via stdio.
Some real life examples, were the Xerox PARC workstations (Interlisp-D repl, Smalltalk transcript, Mesa/Cedar devenv), AmigaDOS shell with REXX, OS/2 with REXX as well, Native Oberon with its command modules, and for something more up to date, Powershell with COM/DLL/.NET/OLE Automation/WMI integration, AppleScript / Automator.
In modern UNIX clones something similar could be achieved via DBUS, KParts and a scripting language of your liking, like Python, Ruby whatever, but it remains a niche thing.
https://www.freecodecamp.org/news/python-for-system-administ...
Ignoring REPL based workflows, structured IPC with GUIs apps for automation, ability to use any library directly, cramping text into a little window in a high definition screen.