> Enrollment != graduation and licensure.

> More people may be interested but nobody can practice until after residency, and you have a large pool of hopefuls basically in a lottery for residency slots.

But my understanding is that residency capacity is matched to graduating class sizes, at least in the US. The selectivity is intentionally placed up front (at med school admission) so the path is clear to residency and licensure as long as the student doesn't totally fall apart (which the selectivity is supposed to guard against).

IIRC, it's foreign medical school graduates may have trouble getting a US residency.