It appears it's not far from the truth. According to https://www.britannica.com/story/nuclear-exclusion-zones it's 4100 sq.km. for Chernobyl and 371 sq.km. for Fukushima (800 sq.km. at peak) which isn't an exaggeration. Interesting.
i guess we think of different things when we read "barren nuclear wasteland".
I see. You weren't saying the size was exaggerated. You were saying that the unusable land was being exaggeratedly described as "barren nuclear wasteland". It's unusable land, so it is nuclear wasteland, but it isn't barren AFAIK.