If it helps, just about everything is like that if you look closely. Processors have side channel attacks, RAM has rowhammer which recently turned out to be a real thing, digital electronics in general turn out to have analog side effects, time and space are both basically impossible for computers to represent precisely (see: falsehoods programmers believe about *). We should do what we can, but life goes on:)
Yep - as soon as they moved away from ROMs I am too.
Amiga, Atari ST and early Macs were sort of in a twilight - they ran the core OS from ROM but loaded utilities and sometimes patches from disk (-ette).