Re: I would imagine at that age bitrot would be a problem, no?
Your 286 motherboard has its BIOS in, most likely, a medium density EPROM. EPROMs degrade, because the charge that defines the '1' or '0' very slowly leaks away across the isolation. The PROMs in an Apple II are low-density fusible-link, which you blow (or not) during programming. Once done, there's nothing that can flip a bit, short of an ESD zapping. I expect the Apple I to have PROMs with even less capacity, with them consequently being even more resistant to bitrot.