I agree with all of this. But! I think it is also important to recognize that there are subgenres where it is significantly harder to find certain things, and it's actively unhelpful to readers to pretend that you can just find whatever type of book you want to read if you just know how to look for it, especially if you are sticking to trad publishing.
It is possible to find both sapphic SFF and M/M fantasy. It is significantly harder to find, say, aro urban fantasy. Or trans romantic suspense. Or intersex mystery.
A lot of the advice above only really works for trad published or popular books and for identities/subgenres/content that aren't too niche.
So here's some advice if the advice above isn't working for you (either because you can't find books with what you want or because the books you are finding don't end up being the vibe you want), from someone who reads a few hundred books a year:
Find websites or lists dedicated to the specific thing you are looking for. They will generally have more variety and will post you to examples that don't show up in regular rec lists. (ex: aro book recs, ace book recs, intersex #ownvoices database, sapphic books). Goodreads lists can (sometimes) also be your friend.
Get comfortable reading self-published and small press books. Trad publishing has its blind spots.
Check Reddit for recommendations
Start figuring out what it is specifically that you like and then start making your searches more specific. This can be subgenre (if you want urban fantasy, you're rarely going to find it just searching "fantasy"), tropes, plot devices, vibes, etc.
Look at the "readers also bought" on Goodreads/Amazon, similar books on Storygraph, etc. if you read a book you like. Even if you don't end up reading the one you click on, it can show you similar authors (similar to looking at the blurb on a cover), especially because far fewer books have blurbs now.
Check out the Literature Map for similar authors.
