IIRC, IA had already been doing that for years. This lawsuit is happening because they stopped limiting digital loans to the number of physical copies IA and their partners had on hand

This is not as legally clear cut as you make it seem. There's plenty of legal discussion around the issue of format shifting books.

It possibly could have, but the circumstances would be significantly different. They did not impose any restrictions this time. If they hadc dinner it as GP suggests, they could easily argue that they made a fair and honest effort to not let closures in the physical world affect library availability. This probably still runs counter to copyright law. Were thr IA to lose such a case, the reasonableness of the approach in the face of such extraordinary circumstances would provide ample impetus to revaluate copyright legislation. Unlike the current situation.

Basically: No one likes throwing the book at the heroes; if the bad guys force that, society may start rewriting the book.

Email? I expect managers of library systems were still checking their email even when their buildings were closed.

Telephone, email, paper letter, door-knocking, carrier pigeon, paper airplane through a window, SMS, IP based messaging systems, linkedin, facebook messenger, verbally.

The same way you get in touch with any other institution composed of people.