> they each have a profile Absolutely true that languages are built to fulfill specific roles and have associated trade-offs. I think you answered your own que

> they each have a profile Absolutely true that languages are built to fulfill specific roles and have associated trade-offs. I think you answered your own question - JavaScript's strengths are being very widespread in current software development and having a minimal syntax/type system. IMO it can be a good language for MVPs/POCs and serve as a higher form of pseudocode. Perhaps the author's choice of JS as a way of reaching the widest possible audience and focusing on the concepts more than the implementation details. A relatively recent personal example: in working through some DSL and parser combinator examples in Rust, sometimes I get too distracted with lifetimes, annotations to deal with deeply recursive functions, etc. and just search for examples in a different language that allow me to focus on the concepts I'm trying to learn.