I am not an expert, but as far as I know this is essentially a lemma/corollary to the anthropic question, ("Why do we, intelligent humans, exist?") which is obviously a Hard Problem.

All answers to the big question I'm aware of, other than religious ones, seem to answer Yes to the corollary. This is largely on grounds of what amounts to a proof by contradiction; if there wasn't an infinite quantity of the conditions available for life, the probability that we existed would be infinitesimal, and it would strain credibility that we existed.