I think the headline is accurate because that is indeed what the study shows, since it compared a control group to a group on a very low calorie diet. But I'd really like to know if this is any _more_ beneficial than more normal, gradual weight loss, like a 2000 calorie diet that gets you down to the same weight.
A lot of people with sedentary lifestyles will gain weight on a 2000kcal diet.
And the heavier you are, the easier it is to lose weight because it takes energy to just maintain all that extra body weight.
Point being, there are certainly some people would not lose weight on 2000 calories/day, but I would guess that isn't true for most of the people in this study.