I don't agree. Theres millions who do/have done Atkins variations. I got my father inlaw on a keto + 1 cheat meal a week4 months ago and he's down 24lbs, with ZERO exercise.
If anything its one of the simpler protocols. Protein + fats....very easy to shop/cook for.
It's simple & effective--no argument here. But adherence to the diet is very low, research backs this up...
It's probably easier for men stick to, since they eat more meat/cheese/nuts than women. But imagine telling granny no bread, no cereal in the morning, no pasta w dinner, no cake on Sundays.... she'd freak out. Plus it's very tough to eat out and find something keto-friendly.
Zone diet is my blanket recommendation for the average individual who's willing to make an effort, but even that's too much portion measuring for a lot of people. Weight Watchers takes all the guesswork out and is the easiest to stick to for the average person.
I think its great that your in-law has had success with the keto diet, but could you honestly imagine telling your grandma that she can only eat green veggies, meat, & fats--and her sticking to it?