Typical philosophy: tear strawman alternatives to prove a wild guess. (Why strawman: because can be also dependent on anything else entirely like positions of copies)

Also, the 99% confidence is not in the dependence on non yous (and yous BUT nothing else), the 99% confidence is in the wild guess of independence from everything else and dependence to count of yous, to be wrong. Also, consider two computer circuits real nearby, running identical you, separated by thin layer of dielectric. Remove dielectric, 1 copy with thicker wires. Conclusion: it may depend to thickness of wires of a copy or maybe to the speed of the copy.

Hell, the probability of being in a specific copy may just as well be undefined entirely until a copy figures out which copy it is, and then depend solely to how it was figured out.

Let's suppose that the probability of being sampled out of model is sum of 2^-l over all codes that pluck you out of the model, like in Solomonoff induction. May well be dependent on the presence or absence of stone dummies (provided those break some simple method of locating you). Will definitely depend to your position. Go show it broken.

edit : actually, this alternative distribution for observers (and observer-moments) based on Solomonoff-type prior has been proposed here before by Wei_Dai , and has also been mentioned by Marcus Hutter. I'm not at all impressed by Nick Bostrom, that's the point, or philosophy for that matter. The conclusions of philosophers - given relative uselessness of philosophy compared to science - ought to be taken as very low grade evidence.