> What if I rely on steam, or epic for P2P and they shutter the service? What if playfab discontinue their offering, or AWS decide to remove a service that our “mini self hosted server” relies upon. Games aren’t some magical piece of technology, they’re just software like everything else.

Not really an apt comparison (since you mentioned P2P), but providing something like HLDS should solve this, no? Counter-Strike 1.6 has long ended its development but it has (or had) a prolific community servers to this day. If Playfab, AWS remove that service, just use your own hardware.