Twenty or more alien hypotheses
This is posted with an expectation of somebody might get some real inspiration to produce a FILM.
The film should make fiction looks real and a scientific fact emerging.
It should hit the audience by surprise and narrow the hypotheses to three or four.
1. Extraterrestrial life is rare or non-existent
2. No other intelligent species have arisen
3. Intelligent alien species lack advanced technology
4. It is the nature of intelligent life to destroy itself
Very likely given time and space
5. It is the nature of intelligent life to destroy others
6. Periodic extinction by natural events
Enough evidence in our planet.
It takes 4 to 5 five billion yeas for life as cells to emerge from stellar remnants.
7. Inflation hypothesis and the youngness argument
8. Intelligent civilizations are too far apart in space or time
It is a real hindrance.
9. It is too expensive to spread physically throughout the galaxy
Not really, if a civilization is threatened at least a significant minority will consider colonizing elsewhere hospitable
10. Human beings have not existed long enough
That is a fact.
11. Humans are not listening properly
More than likely
12. Civilizations broadcast detectable radio signals only for a brief period of time
It could be a deciding factor.
13. They tend to isolate themselves
14. They are too alien
15. Everyone is listening, no one is transmitting
16. Earth is deliberately not contacted
17. Earth is purposely isolated (planetarium hypothesis)
18. It is dangerous to communicate
19. They are here undetected
20. They are here unacknowledged