From this article, it doesn't sound like Hari's books are anything unusual: most topical, with-the-times popular non-fiction is poorly sourced and relies on assertions instead of scholarly or scientific studies — and that's fine! It's okay to have an idea, think about it hard, and write about it, even if you can't prove that your thesis reflects reality. It's better and more worthy of respect if you can, of course, b…
I just wish there was an easy way to find and separate it from actual and more rigorous scientific and expert-driven non-fiction. They often look similar at first glance but there’s a world of difference between, say, Kahneman and Gladwell.