I didn’t read the article except what you posted - but I was waiting for a part to say that in countries where kids are IN SCHOOL longer, there are better results, which would take care of both the homework, and the more practice time.
2. Homework is extremely important.
a. reading assignments with reviews need to be done at home.
b. working math problems and practicing concepts taught at home a must.
c. etc.
This article as presented above is absolutely incorrect and someone or organization needs to expose it for what it is.