What I said (and linked to) was low-carb diets contribute to greater all-cause mortality. And yes, I think keto is a fad diet which will eventually fall out of favor when people have more information about the long-term effects.
It's certainly a good way to lose weight.
I've been on a plant-based diet for 4 years, and have absolutely no trouble maintaining it, because it's easy to get all the nutrients I need from it. The keto diet is hard to follow because you can only eat the carb equivalent of 2 apples to stay in ketosis which very few people actually do. Compliance is extremely low, and no, not all diets are equal when it comes to compliance.
Yes, you can fuel the brain on ketones, so the fact that the brain prefers carbs is neither a myth or debunked. As the study here shows, low-carb diets in the long term lead to a far higher chance of alzheimers, specifically because of protein and mineral buildup in the brain. Not good.
People on pant based diets have the lowest BMI of any group, so not only can you lose weight on them, it's a better way to lose weight and far better for your health. Common sense prevails. Eating loads of fatty, protein dense foods turns out not to be a good idea, which we've known forever. Eating loads of vegetables, fruits, legumes, nuts, and whole grains turns out to be a good thing. What we've known for a long time is still correct. That's why keto is a fad. It just doesn't stand up to the science or results.
https://www.thelancet.com/journals/l...135-X/fulltext