I know of no one who struggles with obesity or being overweight who hasn’t been told to lose it. The weight in itself isn’t bad. See Hibernating. It is conditions that it raises the risk for and reduced mobility which results in less physical activity. I marvel how much easier it is to move when I weigh 325 lbs instead of 420 lbs. Below is a really interesting read on a doctor who has stopped telling their patients to lose weight.