I got the same thing. I installed dbus-user-session and rebooted, then this error message went away and things worked.
- Bug#1013344: podman: The cgroupv2 manager is set to... Elias Batek
- Bug#1013344: dbus-user-session Hans-Christoph Steiner
- Bug#1013344: dbus-user-session Hans-Christoph Steiner
- Bug#1013344: dbus-user-session Hans-Christoph Steiner