I think it really depends on the context. If you are writing about/talking about an experience to elucidate a competency/competencies, then, naturally, the focus should be on the skills. However, of course you can, and should, in perhaps the R of your STAR structure, mention how it furthered an interest of yours!
If the question pertains to motivation, then I think it is important to focus more on the specific interests fostered. A basic chain of explanation could be:
My interest in [xyz] started from [abc] → to begin with, I explored this interest by [123] → whilst doing [123], I specifically enjoyed [456] → this further developed my interest in [xyz] (or something related to [xyz]), which then prompted me to do [789].
In this, you can definitely give your opinions, and it will be important to express what you thought about such experiences. Law firms don't want robotic candidates - they want to hear your opinions and evidence of sincere introspection and reflection!
I hope that helps!
