The only production Go code I ever see is in a kubernetes operator. The backend services I see deployed are probably 75% JVM, 25% Node, and less than 1% something else.
Go is popular at Google, but we're kind of past the point where something being popular at Google makes it popular everywhere.
Google still has LOTS of C++ and Java. Like most companies, we're not going to rewrite large code bases in other languages just because its "new" (comparatively). Greenfield projects can move to new languages more easily.
Twitch.tv uses mostly Go AFAIK. Where I work we use Go in all our services. There's plenty of uses of Go. You just won't ever hear about them, because why would you? You see Java and Node because that's all you've ever worked with. I see Erlang, .NET and Go, because that's all I've ever worked with.
Go is popular at Google, but we're kind of past the point where something being popular at Google makes it popular everywhere.