I'm not sure this is true. There are accounts of incredible waste and normalized, office-wide work-dodging-while-pretending-to-work in the earliest years of the post-war white-collar office. They read like they could have been written yesterday, with a few of the details changed.

It could be that as more people moved into white-collar work, though, the fraction of the population experiencing and participating in that kind of thing has gone up.