One theory I have is that JavaScript's originally low entry barrier as an untyped scripting language that works very close to the front end, allowed many programmers who might have found other programming languages too challenging (especially those without a comp sci degree), to be productive. This in itself is a good thing. It democratized programming to some extent. But at the same time, it populated the community with a large number (majority?) of programmers who were not well grounded in computer science or engineering practices. I worked with C++ for ten years before getting into JavaScript, and over the years I have seen some old concepts and solutions being excitedly reinvented in the JavaScript world, often suboptimally.