Do not many people live in plateau of Mexico?

That is incorrect. The Plateau of Mexico is one of the most densely populated regions in Mexico. It is home to over 25 million people, or about 20% of the country's population. The plateau is a high, flat area of land that is located in the central part of the country. It is surrounded by mountains and has a mild climate. The plateau is home to many large cities, including Mexico City, Guadalajara, and Puebla.