Calling religion a moral compass is a bad analogy. A better analogy is that religions are moral guidebooks. Like a travelers guidebook the major religions describe the situation at a particular point in time. You get commentary on the people and places. The problem is that over time the information becomes outdated. Eventually the landscape will change. The people will change. So the guide bookleads you down dead ends and you will become lost. Of course, some of the major landmarks haven't moved. But, outside of those areas the guide is useless. You cant use a stone-age informatoin to make your way in a modern world.
A better way to travel is to use a compass and a detailed map. That pair gives you the information necessary to make your way. As a bonus the compass and map method gives you neither opinion or commentary. You will have to develop your own opinions as you travel. A difficulty is that unlike the guidebook the map needs updating as the landscape changes. However, getting a new map is easy and you will have current relevant information. Information that you can use
Reducing or eliminating harm is the compass and the observable world is the map. One should always travel towards no harm. However, the landscape doesn't make it easy. For example, we might have a baby poked with a needle to reduce the harm of polio. Using the needle is a small road bump toward reducing harm. Vaccination is a modern part of the map that the stone-age guidebook didn't mention.
The stone-age guidebook is not entirely wrong. It's out of date. The compass and the map are better tools when traveling.
