While I like to think I would thrive being self sufficient, no problems building shelter, hunting, defending myself etc...
Sad truth is one broken cog in the gear train of modern civilization could be pretty bad for even the sharpest guys.
Power grid down unexpectedly means no cells phones or internet for communication we are all dependant on. No way to know what is actually going on or connect with like minds. Freezer shuts off and becomes of tub of rotten meat in a week. Depending on mechanicals, no running water or heat for most. Bank accounts are useless. No gas for vehicles or generators. Mass choas until local resources are depleted or claimed. Then tack on a large chunk of the population being basically helpless and useless that are in the way of the few that even have a chance long term.
But never mind that. I'm taking my electronic fuel injected pickup and machined aluminum bow with carbon fiber arrows into the wilderness this weekend, using electronic maps on my phone to chase elk, unplug, and really get reconnected with the natural world.