This is a fallacy because there is no way to add up 1% savings across 100 employees into an extra full time employee.
Work gets scheduled on short time frames. 5% savings isn't enough to change the schedule for any one person. At most, it gives me time to grab an extra coffee. I can't string together "foregone extra coffees" into "more tasks/days in the schedule".
This. I had the same conversation years ago with someone who said "imagine if Windows booted 30s faster, all the productivity gains across the world!" And I said the same thing you did: people turn their computer on and then make a cup of tea.
Now making a kettle faster? That might actually be something.
Work gets scheduled on short time frames. 5% savings isn't enough to change the schedule for any one person. At most, it gives me time to grab an extra coffee. I can't string together "foregone extra coffees" into "more tasks/days in the schedule".