I think one of the important factors in the Drake equation has to do with the number of stars we estimate in our galaxy and others that are stable, long lived and have planets in the habitable zone. I want to point out that the central parts of our galaxy that are densely populated with stars is not a good place to expect to find even simple life. The reason is that those regions are subjected to such intense radiation that even simple life cannot exist.
I would also suggest that simple life might turn out to be fairly common but it takes an extraordinary and very rare set of events to permit more advanced forms of life, let alone technologically advanced life.
The path of evolution that happened here on earth suggests that simple life evolved or grew a long time, as in billions of years before advanced life forms could even exist. One requirement on this planet was enough Oxygen to support complex life. The simple algae took billions of years to produce enough free Oxygen, that enabled the development of more complex life forms.
Additionally the distances and time to traverse these enormous expanses between galaxies should not be underestimated. It may be that we are early in the universes collection of intelligent life. First to the party so to speak. Even so, the evidence for our existence to others has only traveled a few tens or maybe a hundred light years. Others could not see us if they were further away than that.
I doubt we are alone in the universe but we certainly seem to be in a very exclusive club.