YES, I have been thinking the same and wrote a bit about it: https://vizzly.dev/blog/cli-json-output-llm-friendly/

Thank you so much to the GH CLI for making me realize this, really. The only MCPs I use still are ones that don’t have CLIs. Hell, I even just wrote a CLI for Bear Notes, for LLMs. It’s just better.

Seems like the last MCP use case is model to model communication but I’m sure others have approach’s for that?