for medicine, theres a wide variety of things unis look for such as leadership (being in a team of any sort), teamwork (again, team), communication (anything basically), empathy, professionalism, passion etc.
im not sure for other degrees. medicine is one of few degrees that requires written applications, interviews etc. therefore it is important u have examples displaying these traits in order to have a good chance of getting in.
most other degrees just go by academic merit alone. so even if u had heaps of extracirricular activities, the unis would never know.