Isn't the keto diet just the Atkins diet rebranded? Perhaps with guidance on what fats to prefer, but still, the object is to put the body into ketosis to simulate famine/starvation. I don't know if it's possible for many people to maintain this state for the long term or even to maintain it sporadically for the long term. Besides that, speaking from experience, ketones stink.
"The folks I know who have tried to eat keto for years are all fat, just like folks who overeat carbs. Why? Because folks who are driven toward keto for weight loss have a problem with diet and exercise: they eat too much and exercise too little." That's the harsh reality for many of us who have trouble not gaining weight and have trouble losing it, myself included. For someone who is weight "correct" or close to weight correct, there seems to me no good reason to achieve ketosis. Of course, if someone has a medical condition for which competent medical advice suggests, ketosis, that's different. It's like taking synthroid. If you are hypothyroid, your doctor may prescribe synthroid and in that case, it is a wonder drug. But, don't take synthroid because excess thyroid hormone will help you lose weight. It, also, may make you stink.
My preferred fad diet? Rotel and black beans.