A good reminder that at the end of the day all this CS stuff is just ones and zeros in a chip.
Nothing wrong with the stuff we do today, but I think some of the "magic" of fully mastering a computer and seeing all those raw commands executing at lightning speed (relatively speaking!) was lost.
There is open source tooling for some FPGAs and a fairly small but very helpful community around it.
Yosys, IceStorm, SymbiFlow, and nmigen are the major projects in the space that I'm aware of.
Nothing? There are quite a lot of things if you ask me. As much as things are more complicated out of necessity they are also more complicated for completely unnecessary reasons too.
Typical AVR32s give you 32 bits, 33 MHz RISC for $12. That would have been a decent workstation in 1990.
8 bit microcontrollers have the advantage that most of them are 5V devices vs 3.3V on the 32 bit ones and can also sink and source more current on their pins allowing you more flexibility to hook them up directly to USB Power or LEDs or motor drivers without conversion and from my experience are less sensitive to being bricked or inconsistent behavior from non ideal voltages applied to their pins.
You can freeze the CPU with one pin, single step the whole CPU, etc.
Or things like swapping memory banks, doing something, then swapping it back and returning to the original codepath.
It's neat that it all fits in your head. You can, for any slice in time, walk through all the pin states, registers, memory locations, etc...and fully understand why they are all in the state they are.