So many things are actually concentrated on the "cloud" providers now that significant chunks of "the internet" can all go down at the same time for everyone in a way that was supposed to be impossible with the many-fault-tolerant mindset the internet was originally engineered with. Laypeople don't need to understand any technical topics to understand "a bunch of websites/apps broke for everyone on Sunday". Some are even noting that this is happing more often and affecting more apps at once.
anyways, more on topic with TFA, of course lots of people are looking for excuses for why they aren't what they want to be, and it sounds like this book flips the causation, so that people can say e.g. "I was perfectly healthy until I went through some difficult stuff and now I'm disabled" rather than much more sober but accurate "I was born with some relative weaknesses that make things more difficult for me than others." It looks like he keeps trying to claim that bad experiences leave reliably measurable marks in some way but it simply never holds to the claimed reliability under scrutiny.
Of course, knowing exactly what specific "weaknesses" one actually has compared to a statistical average is the hard part, and jumping to conclusions in that area is just as much playing with fire.
Someone could write a book about "bad experiences give you bad memories, which can bring down your mood when you remember them and demotivate you", but everyone already knows that, and leaving it at that doesn't give the reader the feeling of understanding why they feel less than whole.