"To find early versions of Arial, the Dinamo team had to work with computer technology archivists to get access to some of the first personal computers and operating systems. In the end they found a tool that allowed them to boot up Windows 2000 on their own laptops"
I hope this "technology archivist" charged them appropriately for this monumental task. /s
The interesting thing is that going by that and by Medea's numbers (https://news.ycombinator.com/item?id=45044803), it seems strange that copying from an operating system that was well after WGL4 came out ended up with a glyph list that is significantly short of even WGL4.
By the time that Windows 2000 came out, Arial Unicode had already been published (with Word 2000).
I hope this "technology archivist" charged them appropriately for this monumental task. /s