Does anyone know if a previous flight's passenger name list or passenger name record (PNL or PNR) is publicly accessible?
Edit: I was asking in order to see the number of passengers on the plane after take off, not the identities of the passengers.
No, it is not accessible publicly
The full passenger lists are limited to certain staff members. Been working for airlines for so long and never got that level of access, most likely never will.
Even in cases where some passenger information must be shared, for example, passengers who ask for special meals, a small list of these passengers (seat number, last name and meal type) will be supplied to the crew. It will not be considered PII (Personally identifiable information).
Cabin pursers (the chief cabin crew) might have a list of frequent fliers in first/business classes to be able to serve them more (depending on the airline).
The General Data Protection Regulation (GDPR) touches everything!