You're cherry-picking the epitome of good journalism and comparing it as a class to all books.

The same things that go into writing a good incisive investigative journalism piece or series (many of which ... eventually emerge as books) is what makes a good book a good book. And a book offers time for that process* which a daily or weekly publication focused on current events simply doesn't have. Books trade off timeliness for quality (again, generally). Yes, there are non-topical periodicals which operate with fewer time constraints. Exceptions prove rules.

That is: there's a qualified author, assignment to a given topic, integrity in the pursuit of the story or narrative, research and editorial support in accomplishing that task, and extensive editing and rewriting to produce the most impactful, accurate, and highest-impact piece possible.

Another commonality is that those good pieces run long. A truly in-depth article probably starts at about 6,000 words (12 pages in book print, often less typeset for a newspaper or magazine), and can easily run 15, 30, 60, 90 thousand words, or more.

John Hersey's Hiroshima was published in the 31 August 1946 issue of the New Yorker. I don't find the page-count of that issue though I suspect it was on the order of 80 pages. The book version runs 166 pages, or about 80,000 words.

Hunter S. Thompson's Fear and Loathing on the Campaign Trail was serialised in Rolling Stone before being published as a book, 506 pp, or 250,000 words.

A blog and podcast I follow, The History of Philosophy by Peter Adamson is likewise being produced as a book series. The books add to what's already in the (quite well-produced) podcast.

If we instead look at most or median blogs, newspaper or magazine columns, articles (again, daily or weekly/monthly), or at the top decile of each, I think you'll find, again, that books in general exceed typical quality found elsewhere.

And again, it's not the form but the process.