Okay, I just dove into wireguard‘s source code and it looks like I made wrong assumptions. When I used mullvad or wireguard, it always showed „127.0.0.1“ as the server, however, according to wireguard‘s source, this is just set as a placeholder. I assume that mullvad used this code to implement their app too.
https://github.com/WireGuard/wireguard-apple/blob/13b720442d...