Surely, this has nothing to do with tradition and thus cannot be justified
Usually it's the tradition that doesn't need to be justified... since it's a tradition, it applies. The purpose of prayer call is to be heard, it's been like that for centuries, nothing new. Now they use PA since it's more difficult to reach you with all the surrounding noise and house isolation. Bells are ringing every 30 mins in the church 15 mins from my european house. I never had any pb to fly because of that.