will make many more regions of the earth uninhabitable

Emphasis added. So, not all of it then.

we cannot be certain that human life will remain possible on the planet without being completely dependent on artificial habitats, food, water sources etc.

I already gave the examples of the Sahara an high arctic tundra as places humans can survive. We lived there just fine without advanced technology, even - the Inuit and Bedouin for example.

Again, is the whole entire Earth going to be worse than those places?