>>1926901you're very close! much like how 'you can just walk up to the cockpit of a 747 and talk to the pilot' is one of those pre-9/11 things that just won't happen any more, ever, it's down to international law: the ISPS Code, which was brought into force in 2004.
>https://en.wikipedia.org/wiki/International_Ship_and_Port_Facility_Security_Code...which requires a big, long list of security/border control measures that the kind of places handling sea freight won't be willing to deal with, in order to handle passenger traffic. whereas before they could just hire out cabins to people willing to pay, and leave them to deal with actually getting to the ship etc.
