I don't doubt it's fun. I did a Bachelors in CompSci but had a lot of fun in the few circuits / EE courses that were shared between the CompSci and CompEngg programs.
But sitting at home with an existing job, it's a lot easier to learn C than pick up an oscilloscope and some hardware to run it on. I can't exactly tear apart my home appliances as easily as I can write throwaway programs on a computer.
It's definitely more budget-intensive to muck around with hardware as a hobby, but at the same time, it's perhaps never been easier:
- Lots of used hardware on eBay/craigslist, if you're looking to acquire skills by dismantling or repairing stuff
- Good free tools (i.e. KiCAD)
- Affordable services to order PCBs from
- Lots of businesses selling parts to hobbyists
- Test gear such as scopes and DMMs are now much more affordable, with many low-budget options that are good enough - $1000-$1500 gets you a reasonably complete home lab
- Lots of 3D printing options for encasing what you make
- Large, vibrant communities full of other hobbyists to get help from (or buy used stuff from, if $1000 is above your means)
It's quite satisfying and achievable to build physical things on the side, or build complete systems with your hardware/device components involved.
Another reason it makes for a great hobby: It feels work-adjacent enough (to a software job) to be worth the time investment (i.e. you are gaining useful insights and knowledge that can inform your work as a SWE), while being different enough to feel like a change of pace.
But sitting at home with an existing job, it's a lot easier to learn C than pick up an oscilloscope and some hardware to run it on. I can't exactly tear apart my home appliances as easily as I can write throwaway programs on a computer.