Go is too young, and has extremely small adoption compared to Python, C, C++, Java.  When a language has been around for so long that entire idioms have changed (functional in, object out, reactive in, iteration out etc.), the usage landscape has changed (from desktop scripts up to cloud-scale and down to mobile-app scale), it is natural for the language to have to adapt.<p>The hope is that Go will have enough adoption to require breaking changes!