After my first experience with design systems, I decided to kickstart a project called UI Playbook which is my attempt to document common UI components, their functionality, best practices, accessibility requirements, and examples.
If at least one person finds this useful — it's a win!
I do think there is need for a common vernacular in these components, however I think that too often teams start from scratch when they could pull something off the shelf, and swap out some colors.
List of corporate sponsored design systems: https://designsystemsrepo.com/design-systems/
Totally agree with the Wordpress example, however, I'd argue that more products & applications should attempt to be build upon known primitives to reduce cognitive overload for both the building team and the end users.