Go has done nothing new for fast compile times, like any old timer coder will remember from Algol linage of compilers, with Turbo Pascal for MS-DOS being a good example of how long ago those fast compile times are known.
Even so, I'm all for praising the good things that Go does: if nothing, because of the tremendous mindshare it's getting and the number of people it reaches.
For example, Turbo Pascal 5.5 targeting MS-DOS was released in 1989 and was compiling 34,000 lines/minute.
https://edn.embarcadero.com/article/20803
This is just one example, there are plenty of other languages to choose from with a module based compilation model, only C and C++ toolchains have lousy build times given their textual inclusion model.
http://www.drdobbs.com/cpp/c-compilation-speed/228701711
So the only achievement of Go's compilation speed was making younger generations think it is something extraordinary.