Society needs to do some soul searching and ask why people are so unhappy
What soul? Modern society does not believe in a "soul"
We're just physical matter. We're really no different from animals, or even inanimate objects if you look at it from a molecular perspective
A guy blows up innocent people = rearrangement of molecules
Your thoughts, feelings, experiences, the love that you have for your children, significant other, parents is just just some chemical processes in your brain.
Human beings have no intrinsic value according to the dominant narrative in the modern world.
Also, we live in a consumerist society. This economic model relies on you purchasing things. The more, the better. Do fulfilled, happy, content human beings buy things that they do not need?
This economic model relies on anxious, unfulfilled human beings. Steve Jobs invents the iPhone and in an instant, you have hundreds of millions of people who
need this gadget that they didn't even know about prior to the launch
What is "marketing" other than creating anxiety and dissatisfaction in people to make them buy your product? If you study the early history of modern marketing, you will realize that that's literally what the "founding fathers" discovered.
Modern marketing is literally all about making you dissatisfied with what you currently have and selling you this dream that product x has some intrinsic value that will grant you fulfillment and happiness. A year from now they will repeat the same process to sell you a new product.
If you're rich and have more money than you know what to do with, yet you still have a gaping hole in your heart, where do you go from there? You've done everything that you were told would make you "happy", but you've discovered that it was all a lie. For many people, they no longer see a point in staying alive.