What I see this helping is the proliferation of OpenStreetMap applications. For instance, OsmAND and Maps.me (as I vaguely understand it? Please correct me if I'm wrong) have their own data files served from their own servers, copied from the source OpenStreetMap DB. Periodically, the app developers update the data on their servers, and users soonafter get those updates. (I like this system at least as an option; offline maps are convenient and at least in theory more private.)

Where it gets interesting is if you fork the program. Perhaps OsmAND and Maps.me aren't so fond of having their data used by forks of their applications, for whatever reason. This creates a pretty major barrier for people who want to make a fork; they now have to maintain a data server. (Fortunately for F-Droid users like me, there is a fork of Maps.me simply called Maps. It removes ads, so I imagine Maps.me isn't interested in subsidizing it in the form of server access. I'm not sure what they worked out as far as storage.)

It always occurred to me that they could mostly solve this problem with bittorrent. But if the entire database is torrent-like with Peermaps, that's even better. It could remove one of the barriers to experimenting with new apps. Or so it seems to me.