Earlier quoted context omitted.
How is using fake IDs to board airplanes a joke? Only because we are mostly sure this particular man is an innocent manchild, but how exactly does that generalize?
I don't recall if it was specifically 9/11 that it changed, but I definitely recall that you did not used to have show to ID to get on a plane at all. And at some early points when you did, it was more just like kind of informally showing you were the ticket-holder, not really about security. His "fake ID" saying he was a "laser inspector" is really just an employee ID for a very unsuccesful business he started, righ…
The requirement for a passport and appropriate visa on international flights departing from the UK is I think solely an airline requirement, as if you land in a country you don't have a right to immigrate to the airline gets fined. If you're flying privately it's a different matter.
Obviously you need a passport or other authority to travel when you get to the border of another country (Ireland being the obvious exception for the UK).