Totally anecdotal, but I took escitalopram (the first depression medication mentioned in the study) for years. It worked all right for a while but I was always very low on energy, and after a while it stopped working for me. After some trial and error my doctor and I landed on bupropion (which is also used for ADHD treatment) and it made an enormous difference. I would absolutely believe there is a lot of overlap in treating the two conditions, especially for helping with the the willpower/doing things side of the symptoms (e.g. having energy to do anything in the first place, completing tasks that need to get done, overcoming executive dysfunction, and not getting "stuck" in negative thought spirals).

But of course, it depends on each person and their kind of depression. My doctor warned me that it could make anxiety worse, for example, because the added focus and energy could feed right into someone's anxiety and make them feel mildly panicked all the time. It's highly individual.