LinkedIn networking when you're an introvert
medium.com
medium.com
I guess partly it's because they can - you can list languages and frameworks, where other professions might not have something so clear-cut. But equally, it makes it very hard to distinguish between any number of people who list, say javascript, React, Vue etc. etc. as skills.
So I think it's a proper skill, talking about what you do and what you know, and targeting that to people for whom this adds value (and can therefore generate new career opportunities).
For sure I know it had taken me a long time to learn, and in the back of my mind I always have that version of me who didn't know how to do this.
The point is that building solid professional networks is hard for most people, because it's an awkward social setting. It's the built-in awkwardness that manifests shyness. That's why the emphasis throughout is a structured way to remove the awkwardness, by turning it into something more of a repeatable process.