Reasoned from an employer, the economic optimum consist of two parts:
1) The time you work is spent doing meaningful things.
2) The amount of hours equals the point where if you'd add hours, the negatives outweigh the positives.
In that sense it's bizarre how both parameters don't seem much of a priority. Entire armies of office workers are stuck in zoom meetings and email, seeing most of their day cut up into tiny slices where you can't do focused work. It's quite common to hear that people do about 2 hours of actual work per day.
Rather than obsessing over some ancient number of hours "present", shouldn't effectiveness be an absolute top priority? Not only do managers not seem to care that their employees do little real work, they actually believe that those small blanks in your calendar means you're not busy enough. Have some more meetings. Let's collaborate more!
Here's my "CEO for a day" solution:
A system will for each meeting calculate its cost, which would be the amount of participants multiplied by their hourly rate. Since a 1 hour meeting really costs about 2 hours of productivity (just before and after meetings, nobody does work), the sum would be multiplied by 2, or 1.5 at least.
Once per month or so, you check the aggregates, starting with the worst offenders. It looks like Tom organized about 30K worth of meetings last month. Now Tom is going to tell the company what tangible value he produced in these meetings to offset this.
You'll soon find that it's all power laws. A small group of people responsible for flooding people with meetings.
And you can do the same with email. Efficient workers sent perhaps a handful of emails per day, yet Tom seems to be sending 50-100, all day and night.
Perhaps Tom should shut the fuck up and not mistake his joy in communicating with people for work.