The use of survival skills is not even remotely limited to living on the forest floor under a pile of debris without any modern conveniences. Nor are they limited to being lost or stranded in the woods. In the broader sense, these skills are a means of becoming less dependent on the faltering system and therefore more self reliant. Self-Reliance is a lifestyle, not a technique. The ultimate test is not simply coming out alive but rather going into the mountains as a means of long term survival while the rest of the world reassembles.
There are two primary reasons to study and practice wilderness "survival" skills.
In most instances, technology and a little preparation can eliminate the need for a lot of training for an otherwise unlikely event. Never enter the woods without covering the basics, then you will never have to experience being lost or stranded with nothing at you're disposal.
A navigational device can nearly eliminate the possibility of getting lost but becoming stranded is a risk all outdoors-men frequently take. Packing a water filter eliminates the need to boil water. Carrying rations and packing a modern weapon may otherwise eliminate the necessity for you to learn how to build primitive weapons or traps to obtain food. Carry a Ferrocerium rod fire starter or waterproof matches and there won't be a requirement to start a fire with sticks. Knowing how to start a fire in wet conditions and knowing how to build a temporary shelter remain vital and important. Of course, your tools can become lost or broken and supplies can run out. Learning to build shelters, light fires and obtain food with primitive methods is not a waste of time but planning ahead for the unexpected can be even better.