Healthy people probably have no need to go full keto, although there can still be health benefits by being in nutritional ketosis part time even for healthy people.

A metabolically healthy person will normally produce at least a low level of ketones during the night while fasting between the supper before and the next meal. That is the way it is supposed to work. Store a little fat during the day, retrieve it for energy when no food is being consumed.

Insulin resistant people lack the ability to do the retrieve part.

Going on  a low carb diet reverses the insulin resistance and lets the body operate like it was designed.

If you are taking blood pressure medicine, you may have to get the dose adjusted or get off it. Reducing insulin resistance reduces blood pressure. A lot of people going on a keto diet get off their blood pressure medicine. I got off two.

John