Yes, it can be tricky. But this is true of all information sources to some degree, and the problem is usually solvable with simple heuristics and some search effort.

I've found Amazon (or other website) reviews to be a fairly helpful guide. It's important to read the reviews themselves, to see if you fit with the reviewing audience, before interpreting the numerical ratings.

I've also had success simply searching for "best X textbook", or "best X textbook for beginners". Look for discussions on specialist sites (like MathOverflow, or a physics forum), or recommendations from academics with proven communication skills.

One dilemma specific to academic textbooks is that beginners have only read one or two books, while experts have read so many books they have forgotten what it is like to be a beginner. Another problem with textbook recommendations is that people recommend really dense books to signal their intelligence.

Edit: If anything, the reviews of popular books are more likely to be hyped and biased for irrelevant reasons than reviews of textbooks, once you filter out the people who were assigned the book in a class they don't want to take. For example, popular books on psychology versus a Psych 101 textbook.