It's fairly common to want P2P connections, even if the users aren't aware of it. A lot of online games rely on NAT traversal, sometimes automatically picking a host based on whoever's NAT it can get past. I don't remember the details, but even the Nintendo Switch cares about NAT.

A lot of would-be P2P applications end up using a relay server to get around that restriction, which adds significant cost and latency. Sure it's a well-established workaround by now, but it'd be nice not to rely on it.