100% guaranteed to make me more productive per hour worked. On average, with 8 hours fewer of work per week I would still get the same amount of work done, but would be tremendously happier with my life and with my job.
This change can't come soon enough.
I stopped doing side jobs years ago, when I realized that the money wasn't enough to get my mind in that groove, let alone go somewhere and do something for someone. Now I'm getting to the point where I question if my FAANG salary is enough to justify 40 hours/week.
Spend Friday morning wrapping up the week, making to-dos for the next week, no meetings, minimal email, and generally shutdown for the day by lunchtime.