I do not have data, but from first glance, if anything, the overall demand for self-help and self-improvement increases Y/Y. We can correlate it with a sharp drop in alcohol sales, or raising revenues of therapy industry or fitness industry. YT and podcasts still looming too.

But the form of books … Yes, by some reason it collapses. I personally attribute it not to “people realise those guys are salesmen”, but with the fact that none of really good ideas were produced by such books for a while. Now anyone who really has a new angle or new idea to say — they go straight to YT/podcasts, bypassing writing a book altogether. Because of this, me personally, when I check bookshelves, do not see any really new or interesting idea published in the field.