A couple of thoughts on this one. I think it is worth putting this in its historic context. Most of this code was written at a nascent point in JS history whe

A couple of thoughts on this one. I think it is worth putting this in its historic context. Most of this code was written at a nascent point in JS history where NPM packages could start to be shipped to the browser (i.e. the Browserify years). This was a pretty wild time but one of the concerns was about the amount of code being shipped to browsers (this is pre-tree shaking, which only really works with ESM). Additionally, the glaciation of the JS runtime and standard library at the time, alongside the NodeJS "Cambrian Expansion" of npm, meant lots of authors were working to build out packages that fixed these classes of deficiencies (another example being the now infamous left-pad). We saw the same thing about the same time in the PHP world with the MicroPHP manifest and Composer, and I believe there was cross-pollination of ideas between these two things. It is also worth noting that a decent proportion of people entering into the JS world at this time were more traditional HTML/CSS designers, maybe with some backend experience, but usually not engineers with a strong programming background (my experience, mileage may vary). Looking at the chain of dependencies, the underlying logic of `is-number` is both common enough and a big enough footgun for those particularly less experienced JS developers to warrant a module. And once you've got it, need to do something with it, and once you've got things depending on you, you can't take it down; and thus, a house of cards is built. Lastly, I think its worth keeping in mind that this also tracks with an industry shift to GitHub and an explosion in MIT Licensing/sharing in a world untarnished by the kinds of supply-chain attacks a good deal of us are now rightly worried about. We take it for granted now, but GitHub was a huge change to the way FOSS happens, and that facilitated this kind of repo building (free hosting, free publishing to NPM, sharing culture etc).