This. This is exactly it. I could earn a bit more money working 40 hours, but I decided to do a 4 day work week with only 32 hours and my health has increased drastically.

What's funny about this, is that I'm also a coder and I used a lot of my spare time and regained power to learn new tools, frameworks and programming languages outside of work. Ultimately, these will result in higher paid jobs. Can't do that when you're constantly tired.