I don’t think these hypotheses are mutually exclusive. Low metallicity in the past might explain how we could be first even though the galaxy is very old. The c

I don’t think these hypotheses are mutually exclusive. Low metallicity in the past might explain how we could be first even though the galaxy is very old. The conditions did not exist until recently, on cosmic time scales. If the probabilities are also low then you’re not going to get many even when conditions are right.