It isn't BS as I've lost a considerable amount of weight in a very short time on it, eating nothing but vegetables and meat. Usually eating (far) over 1,000 calories per meal, dripping tons of butter on literally everything, 3x a day, going from 223lbs to 180lbs in 3 months.

I know nearly a dozen people at work who've lost as much or more weight than me, eating like I did. In fact you're the first person I've ever heard of gaining weight on keto, on or off the internet.