I have friends who are, but when GP said "a large percentage of the population", I assumed they weren't specifically talking about clinically depressed people, who don't make up a large percentage of the population. Meditation isn't a cure and it's not equivalent to therapy, so people who are depressed should consider doing things as prescribed by a psychiatrist. Their issues with motivation (such as avolition) aren't issues for most people who don't meditate. Time and addiction to instant gratification probably are.