The problem is that isn't true. The amount of people helped is generally lower than the amount of people harmed, at least with longterm use of many of the major psychopharmaceutical drugs. The book the blog is promoting explains this quite well.

Just this morning there were a flurry of articles on a new study showing that the most commonly prescribed sleeping pills raise your all cause mortality 3x - 5x, and that's over only 2.5 years. One can only imagine what the all-cause mortality over 10+ years is.