How bad could it be?

How bad could it be? Scientists have never established a link between previous pole reversals and catastrophes like mass extinctions. But the world of today is not the world of 780,000 years ago, when the poles last reversed, or even 40,000 years ago, when they tried to. Today, there are nearly 7.6 billion people on Earth, twice as many as in 1970. We have drastically changed the chemistry of the atmosphere and the ocean with our activities, impairing the life support system of the planet. Humans have built huge cities, industries and networks of roads, slicing up access to safer living spaces for many other creatures. We have pushed perhaps a third of all known species toward extinction and have imperiled the habitats of many more. Add cosmic and ultraviolet radiation to this mix, and the consequences for life on Earth could be ruinous.

But, don't worry, the market will take care of it.
https://undark.org/article/books-alanna-mitchell-spinning-magnet/?_utm_source=1-2-2