[jwarkentin]

It seems that OP thinks the asynchronous nature of JavaScript was meant as a performance optimization. Let's go back to its origins. It was originally a scripting language for the browser. If it were to be synchronous and/or allow blocking things, such as `sleep()` or whatever else, it would have created an unusable web experience. Web pages would be constantly locking up. It's only recently that it's moved to the server where the asynchronicity on I/O isn't so mandatory.

I personally still think it's a good thing, but that could definitely be debated on the server side. Unfortunately, if you want to have the advantage of writing one code base that can run on the browser or server, then it must work the same in both places.