The letter to the editor is about 1st grade, not high school.
I agree that 1.5 hours of homework is way too much for a 6 year old - however in many ways it is just a thing.
When my 6 year old sits down and does her homework she can knock it out in 10 minutes. But when she get's it in her head that she doesn't want to do homework, it can take up to 3 hours to accomplish what she is capable of doing in 10 minutes. I go through that scenario at least once a week.
"I go through that scenario at least once a week."
Think of it this way: Kids are taught the same subject year after year and not much changes. They get bored to tears.
The one advantage, a serious advantage, is that home schoolers can cover a wider range of topics than public school teachers are allowed to. Homeschoolers can find the true interests of the child instead of treating every child as the same. Homeworks can be funm, not just the same thing over and over again.
I know a bunch of decent public school teachers; it is the system they must operate within that is seriously broken.
I pulled mine out of Catholic school over excessuve homework in the primary grades and numerous other issues.