Again, the main reason is: you are dealing with tech and biologicals you know nothing about. You DON'T want to be the Alien movie. You DON'T want a pandemic on your ship. And you DON'T want some nanite taking over your crews brains.
Dealing with the unknown, on an interstellar level, means total surveillance is the minimun for safe operation. Get a crew (and players) that you trust for that. I'm not playing traveller to have secrets from my companions. I'm not in it to 'gotcha' the people that im there to have fun with. But the universe, that the ref can and absolutely should, have unknown threats against us? Yes, i want to do the bare minimum to protect against them.
Dealing with the unknown, on an interstellar level, means total surveillance is the minimun for safe operation. Get a crew (and players) that you trust for that. I'm not playing traveller to have secrets from my companions. I'm not in it to 'gotcha' the people that im there to have fun with. But the universe, that the ref can and absolutely should, have unknown threats against us? Yes, i want to do the bare minimum to protect against them.