The video demonstrates the interoperability of gRPC across different programming languages using the same protocol buffer files. The instructor shows a practical demo with services implemented in Go and Java, proving that a Go server can communicate with both Go and Java clients, and vice versa. The key takeaway is that gRPC is not tied to any specific language, as long as the protocol buffer files are consistent, allowing for seamless cross-language communication.

What new insight or understanding did you gain from this video?