Overall, hooks allow libraries to package custom behavior. The `useSelector` hook mentioned above is a React-Redux-specific API that manages subscribing to the store and re-rendering the component when the requested extracted state value changes. So, the "proliferation" you're talking about here is simply libraries and individuals building their own specific logic on top of React's primitives, in the same way that users build specific components on top of React's component primitives.
Brian Vaughn did create `react-virtualized` and `react-window`, but he maintains those separately from his status as a React team member.
React Hook Form is from a community member named Bill-something, I think.
Out of curiosity, what gave you the impression that RHF might be from the actual React team?