I used to be an Apple service technician. We kept an old mac that had SCSI in an expansion port and Ethernet in another for precisely this reason.

I once transferred all 20MB of a Mac Plus hard drive, an author’s lifetime work, to a new iMac with this method.

That's pretty delightful, to think of someone using a computer as such a pure tool like that (as opposed to a distraction machine as is so often the case).

I like to imagine the author finally hit the limit of the 20MB hard drive, then decided, "you know what, rather than put 2 spaces after periods, I'll replace them all with a single space like the kids do", saving 400KB, and making room for at least a couple more weeks of work while shopping for a new computer.

Using ASCII RS as whitespace between sentences, and only converting it to space(s) for rendering, is the boss move.

That is unfortunately the likely fallback... It just feels so wasteful and inelegant.

I'm fairly confident you could string it together as a scsi-to-firewire-to-thunderbolt chain, potentially with a TB2/miniDP-to-TB3+ adapter as well, but this seems even worse to me.