What, in your opinion, is more important to understand? The way Bitcoin works, or what Bitcoin offers? "Both"! Doesn't count.
I know that both are important, but what holds the edge? Of course, that's somewhat situationally dependent, too, however:
I think that understanding how Bitcoin works, gives one the edge in everyday and personal use, but understanding the why to Bitcoin, gives one the edge in debates, fending off critics and orange-pilling no-coiners.
If you'd have to choose something to start with, what would you choose?