When I heard the equation, it was just something else to remember long enough to regurgitate it onto an exam. I wish I had had the foresight to think to ask this question.
When Drake created the equation, I think there was a mid-century assumption bias that technologically advanced civilizations would be immortal (the civs if not the constituent biologicals). What about an extinction rate? Yeah, it could be partially accounted for in L, but I think it rates its own variable. Maybe c really is a hard wall and macro-biological travel across the gulf of stars is impossible. If this is the case, home stars will will eventually die, violently or slowly in the case of the sub-fusion brown dwarves.
When Drake created the equation, I think there was a mid-century assumption bias that technologically advanced civilizations would be immortal (the civs if not the constituent biologicals). What about an extinction rate? Yeah, it could be partially accounted for in L, but I think it rates its own variable. Maybe c really is a hard wall and macro-biological travel across the gulf of stars is impossible. If this is the case, home stars will will eventually die, violently or slowly in the case of the sub-fusion brown dwarves.