I can't see what system is getting/assigning the IP. There are files from both NetworkManager and netplan in /etc but they both seem incomplete and systemd is not running. There are very few processes running and the network-managerinit.d script reports it is not running. There is no /etc/network/interfaces file.
My understanding is that WSL2 has some special kind of DHCP server via the WSL virtual switch but what is contacting that server and getting an IP?