[djur]

Both of them are open now. In 2009, it was possible to write a guide to writing software in Go:

https://web.archive.org/web/20091113154825/http://golang.org...

That looks a lot like today's Go. All of the major design decisions were made, distinctive Go concepts (slices, maps, interfaces, goroutines, switching on concrete type, etc.) are all present. Most of the code examples would compile today with only a few tweaks (if any).

Suffice it to say that Rust was not in that state in 2010. It was barely in that state by 2014. Go was released as a beta; Rust was released as a pre-alpha. That isn't a judgment of either language or community.