Everything PyPI has should be public

I don't think that's true for gaming: players will launch DoS attacks against any other player or server whose IP address they know, to gain a competitive advantage or to harass somebody or simply to be annoying in general, so it's much better if you can hide the IP addresses. There are services like the Steam Datagram Relay (https://partner.steamgames.com/doc/features/multiplayer/s...), where every peer connects to a nearby Steam relay server and can then send traffic to other peers via some persistent user identifier (the SteamID), which gets routed over Steam's private network.

That network can be optimised for latency, rather than bandwidth or transit cost, so it often gives better performance than a direct IP connection between peers. I presume there's some built-in DoS protection - every peer is an authenticated Steam user so it's much easier to rate-limit traffic and to detect and block abuse, and the worst you can do is DoS the relay server itself over IP, which doesn't really matter since peers can just switch to another relay server. It also avoids the pain of port forwarding / NAT hole punching.

There are similar services from Microsoft, Unity, etc. It would be nice if this didn't depend on the small number of gaming companies that are large enough to have a global presence for hosting relay servers, but it seems this is the best we can do on the current internet. If you were designing a new internet from scratch, I hope you'd have better support for this.