There are downsides to any diet. Keto has the huge upside of cutting out nutrient-poor highly processed foods that many people do not even realize are unhealthy.

Also, the idea of “unhealthy fats” is debatable [0], but that is besides the point: the largest downside to Keto is restricting a moderate amount of carbs from healthy choices, from your citation:

> meeting the diet's requirements means cutting out many healthy foods, making it difficult to meet your micronutrient needs.

[0] https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-mi...

Leaning in on old data and recommending people eat copious amounts of saturated fats is just as poor a diet choice as highly processed foods. [0]

[0] https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-h...