Depends on the domain you are interested in. For example, in the physics realm, books by Susskind, Penrose, Weinberg, certainly are not generalizations. Even Smolin, Greene, and Carroll are very experienced in their fields though more accessible than Penrose. Same with computers and programming, innumerable choices are available. Math? Anyone from Ian Stewart to Tao to Hardy. Generally, I’ve found the answer on the overleaf. If the book is written by a science journalist, a reporter, etc., it’s usually a bit light while books written by academics in particular fields, even if written for the general public, are typically “beefier”.