Hmm, ok - what if it wasn’t meant to sterilize the planet, but instead annihilate the food chain and create such an interruption to continuity that the dominant life form (Space T-Rex) gets wiped out?
Why no one has bothered us, the planet is already listed as “Solved” so there is no need to bother.
The aliens would have to be stupid to list a planet as solved for tens of millions of years after killing off the dominant life forms, because, well, a new one will just evolve in short order, exactly as has happened on earth, and they ought to know this.
Hmm, ok - what if it wasn’t meant to sterilize the planet, but instead annihilate the food chain and create such an interruption to continuity that the dominant life form (Space T-Rex) gets wiped out?
Why no one has bothered us, the planet is already listed as “Solved” so there is no need to bother.
The aliens would have to be stupid to list a planet as solved for tens of millions of years after killing off the dominant life forms, because, well, a new one will just evolve in short order, exactly as has happened on earth, and they ought to know this.