UPnP not successful on Xbox Series S

The execution of UPnP across an todo IPv6 network is possible. T-Mobile runs their network as an IPv6 network and also uses 464XLAT to handle IPv4 traffic with the CLAT/PLAT translation. The use of UPnP allows the devices to automatically set port forwarding rules for themselves so this does present some interesting security challenges due to attack vectors. It may/will come down, in part, to how the bandwidth across the n41 cells is handled for a mutually shared distribution and subscriber volume/load. Of course beyond the cells the load on multi-gigabit fiber backhaul routers and negotiations for bandwidth allocations out across the internet routes are sure to be a part of their considerations. Expanding the 5G delivery and the capacity to the edge will take time as there are lots of factors to contend with. Even if/when the bandwidth capability to handle more to the edge is achieved how well will these gateways currently in service handle the demands? Will T-Mobile actually improve and expand the services for games across the 5G cellular delivery? Probably at some future time gaming delivery will improve and expand as the market pressure for a greater subscriber base to feed the machine mounts. It will probably not move as fast as users would like but over time it will probably improve. 

As long as IPv4 and NAT with port forwarding is involved it is unlikely to happen any time soon. Who knows really? T-Mobile has expanded their 5G delivery at an impressive rate. We may all be surprised.