This probably says more about yourself than these websites. Identity should go beyond visuals...
Unless your audience is entirely the blind and partially sighted, visual identity is pretty important
I opened a couple of text heavy ones and they all had different font choices and minor variations on page layout. Most of them had elaborate and unique chapter headings.
Book typesetting is a fascinating subject, I would recommend anyone who works with websites to look into the way typography influences the reader's subconscious. (Maybe we'd have less Helvetica spaffed all over the internet!)
To me, paradoxically, it reached a point where my subconscious associates light or poor typography with serious material, and pretty web pages with empty ad-ridden content:
Serious vibe: http://fmwww.bc.edu/repec/bocode/t/transint.html
Intermediate vibe: https://drewdevault.com/2023/06/30/Social-and-parasocial-med...
Empty content vibe: https://www.theverge.com/2023/7/12/23792382/google-notebookl...