1. Type safety and inferred types
Go is type safe by default, which allows you to right more reliable code and have better developer tooling, plus with the := operator, you can initialize a variable without having to define its type because it automatically gets its type from the initial value.
2. Performance
There isn't much to be said here, but on most counts go beats both Python and Node.js on performance.
3. Documentation
I'm not talking about the Go language itself, although it does have good docs. I'm talking about Go's auto generated documentation tool, which allows people to document their packages easily and works amazingly with Go's type system.
4. Compiles to binary
If you are making a local program for somebody and they don't want to download the Go compiler, you can make Go into a native binary.
5. Built for the web
Go has built in Http libraries to rival Express.js and has a HTML/Text templating system.
6. Great Concurrency
Go utilizes Goroutines to help developers utilize multiple threads easily.
Conclusion
Go is an excellent choice for any system code, especially http networking and web backends.