The practical application of emptiness is that it allows us to cultivate non-clinging to all phenomena, both physical and mental. Emptiness has two dimensions: ontological and psychological. Ontological emptiness is the fact that all of the “individual things” in the “exterior” world are shaped by a matrix of causal factors (i.e., dependent arising), and thus do not possess self-nature and are impermanent and cannot be clung to for any lasting happiness. Psychological emptiness is the realization that all of our states of mind, whether good, bad, or indifferent, are likewise causally conditioned and thus impermanent and cannot be clung to for lasting happiness. So insight into emptiness, whether ontological or psychological, allows us to cultivate a non-clinging attitude toward phenomena, leading to a serenity that results in the ceasing of the kamma production that keeps us locked in samsara. So yes, emptiness is definitely a stepping-stone to Nibbana.
And Alan, I’m not trying to shill for Mahayana, if that is what you’re insinuating. In fact, it was reading Kalupahana’s book that ultimately led me to Theravada.