That's just your interpretation. Take the equation at its face value and it does allow for life originating around some deep sea vents, like JamesLeonis speculated.
Yes, but we should consider these linkages when setting values. If we assume that volcanic vent life is very unlikely to become spacefaring, we should either leave it out of the "life" term, or leave it in but lower the probability of the "becomes spacefaring" term.
It goes the other way around. The Goldilocks zone is a shorthand attempt at helping us guess how many planets out there are capable of supporting life.
> n_e = the average number of planets that can potentially support life per star that has planets.
The fact that the planet is neither too hot nor too cold would seem to be a major component of this term:
https://en.wikipedia.org/wiki/Habitable_zone