The author notes the success of Go. Go's developers knew when to stop. Go is a mediocre language, but it has all the parts needed for server-side software. That's a big market.

I suspect that part of the success of Go is simply because its libraries are heavily used. You know that the library is serving a zillion requests a second in Google data centers. Major bugs have probably been found by now. Go has one solidly debugged library for each major function. Some other languages have a dozen half-debugged partly finished libraries. I once discovered that the all-Python connector for MySQL failed when you loaded more than a megabyte or so with LOAD DATA LOCAL. It passed the unit test, but clearly nobody was using it in production.

There's an intermediate stop between imperative programming and functional programming - single assignment. Variables are initialized once and are then immutable. This is becoming the default in newer languages such as Rust and Go - if you want mutability, you have to ask for it. This gives you the immutability advantages of functional programming without the run-on sentence syntax. Also, results have names, which improves readability, and give you something to display when debugging.