Earlier quoted context omitted.
I'll raise my head above the parapet and admit that I don't get it. How about just scheduling things? If you want to spend more time on things that matter, just pick a date and time, and get going. That said, perhaps the alluring part was gathering data on one's self.
Productivity is a scam. Jeff Bezos doesn't double his own productivity; he doubles Amazon's.
There are other productive activities besides those that increase your wealth. For example, if I'm trying to learn an instrument, then I would consider practicing to be a productive activity. In this sense productivity is not a scam at all; it's a necessity to live a good life.
Speaking purely in terms of money: yes, doubling the productivity of those working for you is better than doubling your own productivity. But many of us don't have that option. If you are a normal employee, increasing your productivity is one of the few ways to increase your earnings.