It's not incompetence; there's quite literally no other real solution. The sprawl of the npm ecosystem is a result of there being (essentially) no standard library in JavaScript and an intentionally small one in Node.js. As a result, simple problems have to be solved in userspace.

Your application can intentionally choose only to depend on a small number of libraries, but of course those libraries will need to consume other libraries, and so on, and you rapidly end up with hundreds of dependencies in node_modules.

If we wanted to solve this, we could introduce a comprehensive standard library. However, we'd need it to be bundled with every existing browser (and Node.js), which is likely why it hasn't happened.