Keto is, by definition, restrictive. On a keto diet one would avoid the purple sweet potatoes that were an 80% staple for the people of Okinawa, back when they were the longest lived and healthiest people on the planet.

Could not agree more about sugar and processed foods...complex carbs however are the bulk of the diets of the people in all the "blue zones", the regions whose people routinely live into their 90s in good and robust health;)