For younger kids, the TECHNICAL side far outweighs the tactical and physical (strength/fitness) aspects. In fact, in really young kids, it should be almost exclusively technical.
The technical/physical/tactical ratio changes as kids get older and competition becomes more relevant.
At the point, a better understanding of tactics and the physical capacity to compete gain relevance.
If the point of the exercise is winning, fitness and tactics are vital. From what I've seen, surprisingly few older kids understand such basic tactical concepts as "time-and-score," and a shocking number are unfit.
Equally, very few high school soccer staffs actively scout opponents and prepare game plans.