Simpler technology usually means fewer things that can fail, tbh. I expect my Gameboy will probably outlast my GBA-SP which, in turn, should outlast both my DS-L and 3DS (and, technically, if you count that I broke the chassis on my first DS-L, it kinda already has -- although that wasn't mechanical failure, that was just clumsiness).
Even the older consoles have all sorts of things that go wrong with them. Good luck finding a secondhand atari or nes that actually works. Its possible, but most of them need components replaced.
Why would it be hard? I still have my original NES and easily replaced the 72 pin connector to fix any potential blinking screens. I have systems going all the way back past the Atari and the only one to break beyond my ability to fix was an original PS1 when the laser board broke. Granted I haven't used them all recently but still. Retro systems are way more bulletproof than modern platforms.
I have a working Game Gear, VB, and launch day PS2 and PS3. Just gotta take care of 'em and clean them once in a while. Maybe replace a battery too.
Most folks dont do that ---
If they drag you through the mud, it doesnt change whats in your blood