The good old days AREN'T over ...
Take heart and hope my friends, the "good old days" are far from gone.
I am not a professional pilot, though I do work in the aviation industry.
Since September 11th 2001, I have done more jumpseating than ever before.
I have travelled FOC on the jumpseat of an Airbus 300, a Boeing 767, a 737, a Dash8, a Gulfstream IV. In the cargo hold of an F27 and a Let 410. And no, not in Africa! In the UK, Europe, and Australasia.
In at least two instances, I have been completely unkown to the crew and have done so without having to even show ID, though they were advised in advance to some degree.
Only last month I made an in-flight cockpit visit on an A330.
The things that make aviation fun are not gone. Just a little more restrictive.
The aviation world does not begin an end at British Airways. Different companies, and different countries have different regulations.
What it comes down to is a healthy dose of common sense.
Bottom line is, if someone wants to interfere with a flight, they will be able to do so, until the day everyone is marched onboard under gunpoint and strapped into their seats.