The strength of using the julia REPL as a "calculator" is not in doing somewhat trivial calculations like dividing two numbers or quickly multiplying two things

The strength of using the julia REPL as a "calculator" is not in doing somewhat trivial calculations like dividing two numbers or quickly multiplying two things, and that's fine. That's not a goal of the REPL and julia is indeed overkill for those kinds of things. However, if you're mathematically inclined and sketch out a few matmuls like in the OP article, julia does have the benefit of making those kinds of interactions more bearable from a syntactic point of view. That's where it shines. And like I've posted above, if you use certain packages frequently and restart the REPL frequently, why not use PackageCompiler to compile your hot paths into your binary, like described in the article (admittedly at the end)? That way, even the first call in a new session will be fast because it has already been compiled. On top of that, the core devs are very much aware that this is a problem and it's actively being worked on.