The distinction between a wilderness survival situation and an urban survival situation is important. In one instance you are going to have access to lots of resources and materials. In the wild a simple cutting tool may be the difference between your life and death. It could be the difference between shelter and dying from exposure. It could mean the difference between having something to defend yourself with or being vulnerable to animal attacks.
This method of creating a stone cutting tool is also inherent to our species. We have used stones to climb the rung and dominate the world. This method of creating a Hoko knife is documented in this article. Knowing how to manipulate stones is a massive survival skill to have. This is particularly true if you spend time in or around the wilderness.