There are various soft skills I've learnt over my career. I've gotten better at reporting, at presenting, telling people no... But none end up in demand as much as being able to debug. There are always going to be things you don't know and going back to first principles to pick them apart is incredibly useful skill.
It's not about being able to program, rather how to pick apart the common problems to make you more effective. I want to take people through how to think like this, everything from learning the language and keeping a summary swipe file, to how to breakdown, test and re-create.