Also an argument against work in general: the vast majority of people were not doing work the entirety of their 8 hour work days.

Coffee breaks, social media, reading HN, which in WfH means walking the dog, spending a few minutes with your family, doing some yoga stands after a meeting.

And that is perfectly fine. Unless you're very focused and enjoying a particular task, no unassisted human being is capable of being 100% productive 8 hours a day, 40 hours a week. I might be an outlier, but in my experience, max focus can be held for up to 4 hours a day, the rest is low focus work and faffing about.