Very much this. The mythology of Star Wars deems balance to mean only light, with the entire narrative demonstrating why that isn't the case as every time one side rises, the other rises to meet it. Revenge of the Sith is an entire movie about why this conclusion is incorrect, with Yoda, Mace and Obi-Wan even questioning it almost verbatim in dialogue between the three.

Balance in the SW universe actually means balance between the two. Superficially light and dark in the same individual/group. But very few in Star Wars have ever really made that connection and is the origin behind much of the conflict, one side trying to take over the other.