And the issue isn't so much whether or not a programmer can hold the "entire system" in their head so much as, if they don't need to, they can be doing a whole lot more. This is, after all, what computers are good for.
I can do a lot more when I can trust my system to evaluate my code and throw compile-time errors. I can't trust Go's you're system in the same way I can Scala.
I noted the simplicity of the stack mostly to forestall the usual tired complaints about complexity, nothing more. What you call "academic", I call "building at scale."
