Or if they were sufficiently advanced, they could entomb their bodies deep in a planet and observe the universe through VR and small undetectable probes. Or may

Or if they were sufficiently advanced, they could entomb their bodies deep in a planet and observe the universe through VR and small undetectable probes. Or maybe the drake equation doesn't factor in drugs: that once a civilisation becomes advanced enough to stimulate their own pleasure receptors they quit bothering with growing and advancing?