I've just seen a YouTube video of a 777 autolanding. The PVD comes alive during rollout after A/P disengagement.
It wasn't armed after touchdown. If the system is switched off completely after T/O (memo message/s removed), how did it rearm itself with an in-air inhibit?
Different aircraft, different logic.
On the 777, unlike the 744, you can rearm the PVDs once airborne (and you get the memo messages again), they will then unshutter on touchdown.