Editing Openai/6946e998-79f0-8007-9a65-19828450838d (section)

==== All you’ve done with this three-step tightening is: ====
* Make η⊕ more selective about obvious geometric/physical disqualifiers.

You have not yet accounted for:
* Long-term climate stability (billions of years vs. just 100 Myr)
* Plate tectonics vs stagnant lid
* Initial volatile inventory
* Early high-energy irradiation and atmosphere stripping
* Impact history and sterilizing events
* Deep waterworlds vs. dry worlds
* Biological probabilities (abiogenesis, evolution of complexity, evolution of intelligence)

So your modified η⊕ is still a “candidate planet count,” not a “likely inhabited planets” count.

But your suggestion (pessimistic HZ + strict radius + mini-Neptune penalty) is a perfectly reasonable way to:
* avoid obvious overcounting, and
* get a much harder lower bound on “worlds that are at least plausibly Earth-class from a coarse physical point of view.”

And even under that deliberately harsh haircut, you still get Galaxy-scale numbers that are enormous on human scales.