From the article: There was also another reason why setting a story in the present day is more attractive than looking into a future even half a century away.

From the article: There was also another reason why setting a story in the present day is more attractive than looking into a future even half a century away. This was because, said Mr Gibson, using that setting would necessitate explaining away present-day problems such as global warming. "If I write something set 60 years in the future I am going to have to explain how humanity got there and that's becoming quite a big job," he said. Ouch.