I haven't seen the full picture of Go yet, partially by some examples. I found it makes calling multi-threading functions a lot easier. I consider Ruby, Python

I haven't seen the full picture of Go yet, partially by some examples. I found it makes calling multi-threading functions a lot easier. I consider Ruby, Python, Go and Julia are the new generation of programming languages aiming to be quickly picked up and made hands-on working. Can anybody tell me if Ruby, Python, Go supports a full spectrum of functionalities for various network protocols, multi-threading, messaging (sync and async) and concurrent accessing etc. Those kind of functionalities don't only require additional libraries, but also frameworks and algorithms. Maybe by using Jython, JRuby or something like that, they are able to achieve the complete functionalities like Java. According to some research, Python evolved from Lisp, and Ruby is closed to Perl. So why aren't those script-based language more popular than Java/C++?