Did you actually read "Rare Earth"? If you did, I think you misunderstood it. While I agree that Ward and Brownlee's definition of what constitutes a "habitable planet" is far too narrow, it is actually the less important constraint on the development of civilization.

The more important constraint is occasional catastrophic events, such as asteroid impacts and nearby supernovae. I think you are absolutely right that life adapts to the local conditions - if a planet has 100 atm surface pressure, water will be comfortably liquid at 200 C, and life will evolve accordingly. In other words, life fits the box that it came in. But Ward and Brownlee's main point - and I think in that they are right, - is that ANY box gets violently shaken every once in a while. And the more complex life forms are, the less of a shake it takes to destroy them. Permian Extinction 250 million years ago came awfully close to wiping out every multicellular creature on Earth. Recent evidence supports the asteroid impact hypothesis; if that asteroid massed twice as much, Earth would be back to bacteria - and would still be there now.

Good analogy are card castles. On any given day thousands of people throughout the world build card castles. Necessary "environment" is easy to come by - a flat surface with no wind, and several card decks. Yet very few 5' tall card castles exist anywhere in the world. 10' tall ones probably do not exist at all - even though there are endlessly trying fanatics. The probability of something knocking them down before they grow that complex is too high - and grows higher as the castle grows. A vibration from a passing truck won't harm a 10-card castle, but will bring down a 100-card one.