apple is using their private relay service (which presumably obscures client ip from apple APIs, but let's take them at their word on this) for a lot of macos-to-apple connections these days.

...including the connections to xp.apple.com from the T2/M1/M2 updater process during macOS updates. however, i have analytics off, and no telemetry from my machine should be going to xp.apple.com regardless, IP address obscured or not. :/