Ketogenic diets will always be controversial for the simple fact that quitting carbs, sugar and junk food is hard and most people are too weak willed to do it.
That's it. That's where most of their arguments come from. From a place of inability to do it and seething at those who can.
They will bend over backwards to create any rationalizations that consuming carbs is beneficial somehow because they can't stop.
They will cope by counting calories telling themselves that junk food and carbs are okay if you carefully weigh all your rations.
Anyone who's done it for extended periods of time can vouch for its results.