Semi-related, I think Web Packages and Signed Exchanges could have some usefulness outside of Google's caches. One of their spec examples was for verifiable web page archives.

Another idea it could be used for a wifi "drop box" (drop station?) when there's no internet connection around. That isn't uncommon at some popular spots up river into the woods in the US.

The idea is that as people enter the area, they can update the drop station automatically for things like news or public posts with whatever they've cached recently.

I'm pretty sure I read about this idea before the spec was drafted but I couldn't find or remember the site, something like vehicle-transported data.