The time to access those files and migrate them into more durable and supported formats is right now. Or 5-10 years ago for that matter.
> In a perfect world, someone would write a Mac emulator that lets you emulate a High Sierra Mac on Apple Silicon hardware, just like SheepShaver lets you emulate a PowerPC Mac on Intel hardware.
OR... or... there are computers other than Apple's. Computers which could be used to emulate an x86-64 Mac without having to deal with ARM translation because they're x86-64 based themselves.
The author's viewpoint is so Apple-centric that the idea of this digital archaeology happening on something besides Apple hardware didn't even enter the picture.