They are uninhabited by humans currently. They are not uninhabitable as shown by animals and plants living there. And they can also not be called "big parts of the earth" by any stretch of those words.
Especially Fukushima is more of a political issue than a safety one.
> animals and plants
Scientists are on the fence: https://knowablemagazine.org/content/article/food-environmen...
> Fukushima is more of a political issue
A very, very expensive political caprice, if any: https://en.wikipedia.org/wiki/Fukushima_nuclear_accident_cle...