There is no doubt that Go is a good language and it's getting popular more than ever. But NO it's not taking over startup scene yet!

Probably nothing even close to what JS is doing in term of numbers and grow if you want to compare languages by usage. (which doesn't mean anything)

Go is just new and shiny comparing to Java, Ruby, C/C++, PHP or Python.

Nobody is going to write much about why we're building our startup with Java or PHP or C++ cos it's just boring and repetitive! Not cool!!

But hell yeah, You will write when you do Go, Elixir, Rust, or Kotlin cos people are gonna read it.

Depend on what you're going to build and your resources, you will choose your stack and one or more programming languages to start.