Hello Hawk98,
Sorry to hear you didn't get the answer you were hoping for, the feedback you mention could mean one of two things:
You have the leadership experience they're looking for but you didn't communicate that you do well enough for them to feel you do. Leadership and management experience, especially at a relatively young age, will come in many shapes and sizes, and won't always clearly be labelled as such when you think how to answer the question.
Or, you gave accurate answers but have just yet to build up the levels of leadership experience they're looking for.
I'd imagine that at your age they're looking for a range of leadership experience rather someone with narrow focussed but exceptionally strong leadership skills which perhaps a much older person would develop in their career. Do you have anyone in the cadets who can help you look at your leadership experience from a different angle?
I'll let you read the previous postings in this thread to decide whether joining a ground trade and then reapplying for an aircrew role or commissioned branch is a good idea!