For me (as a programmer) it really varies a ton. I used to put in insane stretches, due to the medication I needed to take in the past and that is how I got used to things in college.
Now I work more regularly, but still can put in a solid 6+ hr day most of the time, and yet some days… yeesh I’m lucky if I can get a third of that. So I work more on other days to compensate.
Fwiw I would count meetings that are productive as in organizing things as “work”. Not all are that way sadly:-).
There are a lot of busy work meetings that people love to use to dismiss meetings as a whole, but a well run meeting can both avoid a ton of work and get people onboard with things they were likely to blow off. One project I am running has people volunteering to do work and we have even decided not to do something after getting into the weeds, saving a ton of time. But if we didn’t decide as a group we would have wasted so much time on that thing.
My general rule is that if the meeting exists to let people know what happened, what is coming up, and no decisions will be made it should have been an email. If there will be a group decision or work distributed based on feedback from the group it is likely to be productive.