From what I understand most semi-auto guns are banned in Australia, but of course they never had a ton of those to start with. But there are still plenty of pump action, lever action, bolt action, etc guns which aren't meaningfully less capable. Shooting twice as fast doesn't mean you can kill twice as fast because you can't aim twice as fast. Like the majority of guns Afgan insurgents had were 60 year old bolt-actions which were quite obviously still capable enough to be deadly even to the top military in the world.