There is the argument that homework, a large quantity of homework, is necessary for assessment. I would largely use Cooper, H., Robinson, J. C., & Patall, E. A. (2006) and Cooper, H. (2010) and Terada, Y. (2015) to disprove this claim; it is the quality, not quantity, of homework that best assesses the progress of a student. There are other, more quality ways to measure progress in a classroom than take-home work.
Another argument is for “practice makes perfect”–that repetitive homework assignments are of benefit. I would argue that there is a threshold that is reached where the practice is a hindrance rather than a help. Simplicio, J. S. C. (2005) is a source I would rely on here.
While I would agree that hours of homework is too much for little kids but some times I do feel as some homework isn’t bad. I feel like giving at least some for math especially would be more acceptable. While this homework shouldn’t be advance but it could just be having them practice their multiplication tables. As this is generally something that is heavily, at least I remember it being this when during elementary school, repeated and was quite then repetitive. This at least for me seemed to allow me to be able to memorize them better as a child.