There is a great KISS principle. When you can effectively develop a website using only vanilla CSS & HTML and a bit of JS, why use some overhyped fancy tools l

There is a great KISS principle. When you can effectively develop a website using only vanilla CSS & HTML and a bit of JS, why use some overhyped fancy tools like grunt, gulp, bower, less, sass, yeoman, etc.? I can open vim or any other code editor on any PC and start coding web pages right away, without spending hours on configuring complex toolchains, writing build scripts and so on. If web pages could be done that simple oldschool way 5 years ago, couldn't they be done the same way today? Put it this way: there are still great C99 programmers who make fast programs, are they useless only because they don't use C++14 with all bells and whistles?