I came here to agree and would love to live in a world where what you’re proposing is the norm. Especially with the leftover time for working on building your skills.

However, a few statements were quite contrary to my own experience:

1) I don’t think in my career that I’ve made habit of trying to look busy in the office. Not that it had never once happened, but not making it a regular routine is key. I’d feel guilty for “appearing busy” and being paid for it.

Got downtime or all my tasks done? Maybe I can finally write a script to automate repetitive or tedious tasks that I have been doing manually.

Maybe document some information that’s been siloed for too long. Or just ask someone else if they need help with their tasks.

If you’re working someplace where you’re scared to go home early when your work is done, because the management doesn’t like the way it looks, you’re working for the wrong people. That culture and mindset needs to change, for sure.

2) When I was a fledgling programmer still in college, I could go on 12-16 hours stints working on my extracurricular pet projects. I’d practically have to force myself to stop and sleep; all this without a single drop of caffeine or energy drink. I can honestly say that my cognitive ability did not decrease relatively to consecutive time spent solving problems.

If you can look past my bragging there is a point: if you have passion for what you do, it won’t feel like work, and your brain won’t fight you for making it think.

Of course, that was 20 years ago and I am now burned out. Maybe because of prolonged cognitive efforts, but also maybe because I’m no longer following my passion projects. These days, I’m probably more like the workers in those studies.

So more or less circled right back to agreeing with you, but hopefully this comment was useful.