These are the links so I don't forget:

The Atavist Magazine (Note: While many articles are paid, a selection are often free. Check individual stories.)
Epic Magazine (Note: Many stories are paid, but a selection may be free or accessible. Check individual stories.)
The Guardian US (Offers extensive free long-form journalism, relies on donations.)
The New York Times (Offers a limited number of free articles per month before a paywall. Can often access more by searching directly.)
The Washington Post (Offers a limited number of free articles per month before a paywall. Can often access more by searching directly.)
Medium.com (Many articles are free and accessible without registration; look for those not behind the "member-only" designation.)

Kirkus Reviews (Professional book reviews, free to browse.)
Publishers Weekly (Industry news and reviews, free to browse.)
Project Gutenberg (A library of over 60,000 free eBooks, primarily older works out of copyright. Not a tracking site, but a source of free reading material.)
Goodreads (While personal tracking requires registration, you can browse public book pages, read reviews, and see lists without logging in.)

Reactor Magazine (Your favorite! Excellent for sci-fi, fantasy, horror, and broader genre media criticism.)
Literary Hub (LitHub) (A great aggregator of literary news, essays, excerpts, and criticism from various sources, often including book discussions.)
Kirkus Reviews (Offers professional, unbiased reviews of a wide range of new and forthcoming books.)
Publishers Weekly (Covers the publishing industry, including extensive book reviews across genres.)
The New York Review of Books (Known for its in-depth literary essays and reviews, often free to access.)