L2TP VPN destroyed, domain controllers restart, VMs won't start

The first Patch Tuesday of 2022 set the tone for the year. L2TP VPN connections broke completely. IPSEC tunnels failed. Domain Controllers restarted unexpectedly, taking entire enterprise networks offline. Hyper-V virtual machines refused to start. ReFS media became unmountable. HDR displays broke. In one update, Microsoft knocked out VPN access, enterprise authentication, virtualization, and storage — essentially every infrastructure component a business might depend on. The emergency fix arrived six days later, during which time remote workers couldn’t VPN in and servers rebooted themselves unpredictably.