"I consider the metaphor that Chinese teachers use to illustrate school mathematics to be more accurate. They believe that elementary mathematics is the foundation for their students' future mathematical learning, and will contribute to their students' future life. Students' later mathematical learning is like a multistoried building. The foundation may be invisible from the upper stories, but it is the foundation that supports them and makes all the stories (branches) cohere. The appearance and development of new mathematics should not be regarded as a denial of fundamental mathematics. In contrast, it should lead us to an ever better understanding of elementary mathematics, of its powerful potentiality, as well as of the conceptual seeds for the advanced branches."
Ma, Liping (2009-03-20). Knowing and Teaching Elementary Mathematics: Teachers Understanding of Fundamental Mathematics in China and the United States (Studies in Mathematical Thinking and Learning Series) (Kindle Locations 3013-3019). Taylor & Francis. Kindle Edition.
I wrote essentially the same thing a few years ago, not about Chinese teachers, about how to best teach mathematics.
To say I have put a fork in this pretense of teaching algebra to elementary students would be an understatement. The TIMSS assessments and results are publicly available. So are the PIRLS assessments. Anyone with the wherewithal can take the time to study them, as I did. After that, track down as many textbooks as you can. Then come back and tell me that these countries teach algebra in elementary school.