I think it's perhaps a reference to the original intent of Go at Google. They want new joinees to be quickly productive and also be able to write problem free s

I think it's perhaps a reference to the original intent of Go at Google. They want new joinees to be quickly productive and also be able to write problem free software (and maybe maintain a lot of old software in addition to writing new software). Having more advanced language features is perhaps not conducive to this. Features like templates do take a bit more effort to grok and also take a bit more effort to understand the flow of code when maintaining software.