But isn't the issue that I may have been living in an area for decades and because the government didn't correctly price/deter externalities, now I can't afford to live somewhere? The companies lobbying for the abilities to pollute and otherwise add risk to the world can afford to pay the higher insurance rates. The folks who live in the areas they put at risk often can't.

Insurance costs rising are a good signal, but they're essentially a way to tax normal people for the faults of governments and major companies. It does reflect the real risk, but it's not like the fact of people living in most of these areas is the reason the area is risky.