Same, it is a question of time.

For me, weekends only... I used to do a lot of freelance work (years ago...more than a decade ago), somehow I used to find more time then for side projects... with full time employment is is impossible to find the time.

I have the same problem. For my first several years of work, I works 3x12. This was a dream. I had a lot of time to recover from work and do my own thing. It was almost like not having a job. Now that I work 5x8, I’m basically useless outside of work.

It's not about having time, it's about making time.

One thing that helps me is to actually schedule time to do the cool, fun stuff, put it on my calendar and treat that appointment as inviolable as missing work. Because it is work, and eventually it will become a habit.

I also recently read Time Management for System Administrators which has some other helpful suggestions: https://www.oreilly.com/library/view/time-management-for/059...

There's no definitive answer to this since everyone's situation is different. The best advice I can offer is that eating well (increasing your vegetable intake, cutting back on refined sugars, etc.) and exercising consistently (HIIT, anaerobic training, etc.) can help offset a work-related energy deficit and at least make it feel like you’ve got enough energy for extracurriculars.