Certainly, reasonable limits need to be considered. In older grades where students have multiple teachers, homework can teach students how to manage their time and set priorities. Such a system can occasionally overload students with multiple tasks in multiple classes. A program to articulate homework assignments among a student's teachers would eliminate a burden that may become only an endurance contest rather than actually enrich a lesson. But very young children have short attention spans and need homework in small doses.
Many variables are at work here too.
We encourage schools to set and maintain high academic standards, a component of which should be homework. We can't ask teachers to maintain these standards and then hamstring them with unworkable conditions. The PTA recommends 10 minutes a night per grade level and that may be fine, but some nights it could be more and some less. Rather than trying to determine exactly how much homework is too much homework, educators and parents should work together to determine what is the function and role of homework in a student's academic life. If students are completing worksheets or rote lessons that are returned to school only to be ignored or left unchecked, then the assignment amounts to so much busywork.