For archival purposes, we might as well just archive the software that was used to read it. In fact, we already do to some extent - for example, Debian archives package repos for all its releases, so you can still get Potato (2000) up and running.

There's also the question of hardware, but so long as we have at least one up-to-date PC emulator, we have an answer to that. It might become more of a challenge going forward, as mainstream emulators drop BIOS support and other legacy parts of the platform; but even then there's stuff like PCem.