The Drake Equation has so many fuzzy unknowns that you cant get meaningful information out of it, if rephrased right we could get some meaning variables to play with. If we want to know if there are possible communication partners right now, we can figure out some of the unknowns. First the definition of an earth like planet. It has liquid water and dry land. Liquid water, because the only kind of life we know of developed in liquid water. Dry land because developing a communicating technology requires an abiulity to isolate your experiments. I believe there are so many impediments under water that a technological civilization would never develop. So a technological civilization requires 4B years to develop from the birth of a star. The habitable zone of a star is where water is liquid roughly. An earth-like planet must have inhabited a continuously habitable zone for 4B years. A flare star may not have a continuously habitable zone. An M star's habitable zone may be so close to the start that the planet is in a tidal lock with the star. An enterprising astrophysist can probably estimate the probability of a sufficently large stable habital zone for a given class of stars. We dont have enough data for estimating the probability of a water/dry land world being there.

Given life and enough time, what is the probability of a technological civilization arising. 1.0 or so small that we are alone. We are probably at the age and interconnectedness that we will survive a very long time. I dont wory about nuclear war, but I do worry about bio-terror and nut cases.

I think the big constraint is patience. I dont think any civilization is ready to invest the time and energy to wait 1000 years for a reply. I think the potential partners will be limited to a volume of 100 light years. Maybe 5000 stars, not all that many.