Today, I was painfully reminded to RTFM before upgrading. With the upgrade from Proxmox 8.1 to 8.2, there were some breaking changes:
Kernel: Change in Network Interface Names
Upgrading kernels always carries the risk of network interface names changing, which can lead to invalid network configurations after a reboot. In this case, you must either update the network configuration to reflect the name changes, or pin the network interface to its name beforehand.
See the reference documentation on how to pin the interface names based on MAC Addresses.