What depth actually looks like
Time held, and change over that time. Joining a club in ninth grade, running a part of it in eleventh, and leading it in twelfth is a story. Being a member of five clubs is a list.
It does not have to be leadership in the formal sense. Getting substantially better at something, taking on the part nobody wanted, starting something small that outlived your involvement — all of these read as depth. A title is one way to demonstrate it, not the thing itself.