Yeah, all this analysis (both what we've done and in the original article) are facile--a proper Bayesian treatment would have continuous priors/posteriors that

Yeah, all this analysis (both what we've done and in the original article) are facile--a proper Bayesian treatment would have continuous priors/posteriors that would be a little more informative than an either-or. The problem you're seeing here is that if you make your possibilities "Humans live forever (even past the heat death of the universe)" or "All humans die in the next 10 minutes", you'll find that the chance that humans die in the next 10 minutes is really absurdly high.