This is not true. 6 year old is year 1 in Chinese primary school. Apparently it is going to be taught at year 3, year 5 in primary school, year 2 in secondary school and year 1 in high school.
I haven't read the text, my assumption is that it would be similar to Mao's, Deng's and Jiang's Thought. Why I consider it is about the government? For example, Deng's thought would set modernization as the priority for country's development. Xi's thought would set new priority. It is just how Chinese government works.