While I do agree that MCP was probably bit too far from whats required, there is some benefit for sure. Providing information in a consistent format across all the services makes it easier work with. It lowers the brittleness of figuring out things making the products built using LLMs more stable/predictable. Most importantly it becomes the latest version of the documentation about a service. This can go a long way in M2M communication, pretty much standardization of Application layer.
Oh wait, things like open-api and all already exists and pretty much built to solve the same problem.