PLBs are good at one thing, letting the authorities know you're in trouble and where you are. If you travel over or through remote areas where you are going to be well away from hell they make a lot of sense.

But they have less utility if the problem is that you are one of many people in trouble and/or if emergency services are unavailable or overwhelmed.

A PLB is of less use in most hurricane, earthquake, riot, flood, or wildfire scenarios. Activating a PLB doesn't move you to the top of the list for rescue.

A PLB also won't keep you fed, watered, sheltered.