I don't think you fully grok what they have achieved. Google employs only a handful of people who work on Go, and probably not all them work full time on it (though maybe that's not true lately in the last release cycle).Let me give you a quote from an accomplished (hint, you use his code every day) C & C++ hacker on using Go:
"In my experience Go is probably 5-10x faster than C or C++. I estimate that programs that take me half an hour to write in Go would take me about 2½ hours in C and 5 hours in C++."
Then when you only have to wait about 10 seconds or so for the whole Go std library *and* all your own libs and binaries to build, you can see it's value over waiting for large C++ projects (of which Google has many) to build.
Real programs don't eat cache.