Go needs optional arguments for goroutines and have global defaults because recompiling is ludicrous.

Erlang is an ok language with a great runtime. Elixir is much higher level language and hence more productive for teams that already know Erlang but want to write less code and build faster. Also with Erlang, static type checking not used much in Erlang and big loss unless you use dialyzer. Advantage go for compiling and running test cases laser-blindingly fast. There is a native QuickCheck framework for Erlang, and I'm sure someone wrote a go one.