My perspective is that Go seems to be trying to aim at network aware services where Java might have been used before.

Internally what I've seen @ Google is it seems to be used here and there for services where Google teams have typically used C++ (but other companies might use Java.)

And yes, some places where Python has been used, Go makes a decent replacement.

Not my cup of tea, but I can see its niche. It's not the same niche as Rust. At least not right now.