I agree with you that Go does not replace C or C++, but I strongly disagree that Go is an obvious replacement for most uses of Python, C#, Java or Ruby, all of which are, frankly, _much_ higher level languages than Go.
Go gets used for two main reasons that I've been able to observe:
1) a desire for a very specific type of concurrency
2) a desire for a fast compiled language with a minimalistic feature set that scales well to large teams.
Switching to Go from one of those languages is very much giving up a kitchen sink for a purpose-built tool. It may be the right decision under lots of different circumstances, but it doesn't directly compete with any of the languages you've mentioned because of how minimalistic it tries to be.
Overall, in fact, I think Go does something far more interesting: it's legitimately an attempt to carve out a whole separate niche for software development. Whether it's ultimately been successful there is for a different comment thread, though. :)
Go has always been a high level language, and is even more so now with generics. I would even argue that Go, correctly done, is halfway between the Java tier and the Lisp tier. Due to Go's quick and easy parsability, generation, and compilation. It is very easy to write tools for Go. Code generation and struct tags are even part of the standard, but very people use them beyond the basic serialization libraries. It's not quite lisp, but it is very close in many ways.
Very few people rewrite projects. Most change happens by new projects adopting one language over another. The fact that I hear of Python rewrites to Go is honestly amazing.
Go gets used for two main reasons that I've been able to observe:
1) a desire for a very specific type of concurrency 2) a desire for a fast compiled language with a minimalistic feature set that scales well to large teams.
Switching to Go from one of those languages is very much giving up a kitchen sink for a purpose-built tool. It may be the right decision under lots of different circumstances, but it doesn't directly compete with any of the languages you've mentioned because of how minimalistic it tries to be.
Overall, in fact, I think Go does something far more interesting: it's legitimately an attempt to carve out a whole separate niche for software development. Whether it's ultimately been successful there is for a different comment thread, though. :)