A fundamental principle of the Web is that site-specific clients or apps shouldn't be necessary.

That they are only underscores Google's massive blunder here.

Yes, there've been CLI wrappers around web queries before. Until the past few years, these simply addressed search format, URI arguments, and namespace. They launched in the user's choice of browser, text or graphical. Surfraw is the classic, I've written a few very brief bash functions for equivalent capabilities, again, launching any arbitrary browser (though usually w3m by my personal preference).

Now what's needed, and you're recommending, is a content-side wrapper as well. This story ends poorly.